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-rw-r--r--include/linux/lz4.h762
-rw-r--r--lib/lz4/Makefile2
-rw-r--r--lib/lz4/lz4_compress.c1161
-rw-r--r--lib/lz4/lz4_decompress.c705
-rw-r--r--lib/lz4/lz4defs.h338
-rw-r--r--lib/lz4/lz4hc_compress.c867
6 files changed, 2758 insertions, 1077 deletions
diff --git a/include/linux/lz4.h b/include/linux/lz4.h
index 6b784c59f321..1b0f8ca0f9c8 100644
--- a/include/linux/lz4.h
+++ b/include/linux/lz4.h
@@ -1,87 +1,717 @@
-#ifndef __LZ4_H__
-#define __LZ4_H__
-/*
- * LZ4 Kernel Interface
+/* LZ4 Kernel Interface
*
* Copyright (C) 2013, LG Electronics, Kyungsik Lee <kyungsik.lee@lge.com>
+ * Copyright (C) 2016, Sven Schmidt <4sschmid@informatik.uni-hamburg.de>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
+ *
+ * This file is based on the original header file
+ * for LZ4 - Fast LZ compression algorithm.
+ *
+ * LZ4 - Fast LZ compression algorithm
+ * Copyright (C) 2011-2016, Yann Collet.
+ * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * You can contact the author at :
+ * - LZ4 homepage : http://www.lz4.org
+ * - LZ4 source repository : https://github.com/lz4/lz4
*/
-#define LZ4_MEM_COMPRESS (16384)
-#define LZ4HC_MEM_COMPRESS (262144 + (2 * sizeof(unsigned char *)))
+#ifndef __LZ4_H__
+#define __LZ4_H__
+
+#include <linux/types.h>
+#include <linux/string.h> /* memset, memcpy */
+
+/*-************************************************************************
+ * CONSTANTS
+ **************************************************************************/
/*
- * lz4_compressbound()
- * Provides the maximum size that LZ4 may output in a "worst case" scenario
- * (input data not compressible)
+ * LZ4_MEMORY_USAGE :
+ * Memory usage formula : N->2^N Bytes
+ * (examples : 10 -> 1KB; 12 -> 4KB ; 16 -> 64KB; 20 -> 1MB; etc.)
+ * Increasing memory usage improves compression ratio
+ * Reduced memory usage can improve speed, due to cache effect
+ * Default value is 14, for 16KB, which nicely fits into Intel x86 L1 cache
*/
-static inline size_t lz4_compressbound(size_t isize)
+#define LZ4_MEMORY_USAGE 14
+
+#define LZ4_MAX_INPUT_SIZE 0x7E000000 /* 2 113 929 216 bytes */
+#define LZ4_COMPRESSBOUND(isize) (\
+ (unsigned int)(isize) > (unsigned int)LZ4_MAX_INPUT_SIZE \
+ ? 0 \
+ : (isize) + ((isize)/255) + 16)
+
+#define LZ4_ACCELERATION_DEFAULT 1
+#define LZ4_HASHLOG (LZ4_MEMORY_USAGE-2)
+#define LZ4_HASHTABLESIZE (1 << LZ4_MEMORY_USAGE)
+#define LZ4_HASH_SIZE_U32 (1 << LZ4_HASHLOG)
+
+#define LZ4HC_MIN_CLEVEL 3
+#define LZ4HC_DEFAULT_CLEVEL 9
+#define LZ4HC_MAX_CLEVEL 16
+
+#define LZ4HC_DICTIONARY_LOGSIZE 16
+#define LZ4HC_MAXD (1<<LZ4HC_DICTIONARY_LOGSIZE)
+#define LZ4HC_MAXD_MASK (LZ4HC_MAXD - 1)
+#define LZ4HC_HASH_LOG (LZ4HC_DICTIONARY_LOGSIZE - 1)
+#define LZ4HC_HASHTABLESIZE (1 << LZ4HC_HASH_LOG)
+#define LZ4HC_HASH_MASK (LZ4HC_HASHTABLESIZE - 1)
+
+/*-************************************************************************
+ * STREAMING CONSTANTS AND STRUCTURES
+ **************************************************************************/
+#define LZ4_STREAMSIZE_U64 ((1 << (LZ4_MEMORY_USAGE - 3)) + 4)
+#define LZ4_STREAMSIZE (LZ4_STREAMSIZE_U64 * sizeof(unsigned long long))
+
+#define LZ4_STREAMHCSIZE 262192
+#define LZ4_STREAMHCSIZE_SIZET (262192 / sizeof(size_t))
+
+#define LZ4_STREAMDECODESIZE_U64 4
+#define LZ4_STREAMDECODESIZE (LZ4_STREAMDECODESIZE_U64 * \
+ sizeof(unsigned long long))
+
+/*
+ * LZ4_stream_t - information structure to track an LZ4 stream.
+ */
+typedef struct {
+ uint32_t hashTable[LZ4_HASH_SIZE_U32];
+ uint32_t currentOffset;
+ uint32_t initCheck;
+ const uint8_t *dictionary;
+ uint8_t *bufferStart;
+ uint32_t dictSize;
+} LZ4_stream_t_internal;
+typedef union {
+ unsigned long long table[LZ4_STREAMSIZE_U64];
+ LZ4_stream_t_internal internal_donotuse;
+} LZ4_stream_t;
+
+/*
+ * LZ4_streamHC_t - information structure to track an LZ4HC stream.
+ */
+typedef struct {
+ unsigned int hashTable[LZ4HC_HASHTABLESIZE];
+ unsigned short chainTable[LZ4HC_MAXD];
+ /* next block to continue on current prefix */
+ const unsigned char *end;
+ /* All index relative to this position */
+ const unsigned char *base;
+ /* alternate base for extDict */
+ const unsigned char *dictBase;
+ /* below that point, need extDict */
+ unsigned int dictLimit;
+ /* below that point, no more dict */
+ unsigned int lowLimit;
+ /* index from which to continue dict update */
+ unsigned int nextToUpdate;
+ unsigned int compressionLevel;
+} LZ4HC_CCtx_internal;
+typedef union {
+ size_t table[LZ4_STREAMHCSIZE_SIZET];
+ LZ4HC_CCtx_internal internal_donotuse;
+} LZ4_streamHC_t;
+
+/*
+ * LZ4_streamDecode_t - information structure to track an
+ * LZ4 stream during decompression.
+ *
+ * init this structure using LZ4_setStreamDecode (or memset()) before first use
+ */
+typedef struct {
+ const uint8_t *externalDict;
+ size_t extDictSize;
+ const uint8_t *prefixEnd;
+ size_t prefixSize;
+} LZ4_streamDecode_t_internal;
+typedef union {
+ unsigned long long table[LZ4_STREAMDECODESIZE_U64];
+ LZ4_streamDecode_t_internal internal_donotuse;
+} LZ4_streamDecode_t;
+
+/*-************************************************************************
+ * SIZE OF STATE
+ **************************************************************************/
+#define LZ4_MEM_COMPRESS LZ4_STREAMSIZE
+#define LZ4HC_MEM_COMPRESS LZ4_STREAMHCSIZE
+
+/*-************************************************************************
+ * Compression Functions
+ **************************************************************************/
+
+/**
+ * LZ4_compressBound() - Max. output size in worst case szenarios
+ * @isize: Size of the input data
+ *
+ * Return: Max. size LZ4 may output in a "worst case" szenario
+ * (data not compressible)
+ */
+static inline int LZ4_compressBound(size_t isize)
{
- return isize + (isize / 255) + 16;
+ return LZ4_COMPRESSBOUND(isize);
}
-/*
- * lz4_compress()
- * src : source address of the original data
- * src_len : size of the original data
- * dst : output buffer address of the compressed data
- * This requires 'dst' of size LZ4_COMPRESSBOUND.
- * dst_len : is the output size, which is returned after compress done
- * workmem : address of the working memory.
- * This requires 'workmem' of size LZ4_MEM_COMPRESS.
- * return : Success if return 0
- * Error if return (< 0)
- * note : Destination buffer and workmem must be already allocated with
- * the defined size.
- */
-int lz4_compress(const unsigned char *src, size_t src_len,
- unsigned char *dst, size_t *dst_len, void *wrkmem);
-
- /*
- * lz4hc_compress()
- * src : source address of the original data
- * src_len : size of the original data
- * dst : output buffer address of the compressed data
- * This requires 'dst' of size LZ4_COMPRESSBOUND.
- * dst_len : is the output size, which is returned after compress done
- * workmem : address of the working memory.
- * This requires 'workmem' of size LZ4HC_MEM_COMPRESS.
- * return : Success if return 0
- * Error if return (< 0)
- * note : Destination buffer and workmem must be already allocated with
- * the defined size.
- */
-int lz4hc_compress(const unsigned char *src, size_t src_len,
- unsigned char *dst, size_t *dst_len, void *wrkmem);
+/**
+ * lz4_compressbound() - For backwards compatibility; see LZ4_compressBound
+ * @isize: Size of the input data
+ *
+ * Return: Max. size LZ4 may output in a "worst case" szenario
+ * (data not compressible)
+ */
+static inline int lz4_compressbound(size_t isize)
+{
+ return LZ4_COMPRESSBOUND(isize);
+}
+
+/**
+ * LZ4_compress_default() - Compress data from source to dest
+ * @source: source address of the original data
+ * @dest: output buffer address of the compressed data
+ * @inputSize: size of the input data. Max supported value is LZ4_MAX_INPUT_SIZE
+ * @maxOutputSize: full or partial size of buffer 'dest'
+ * which must be already allocated
+ * @wrkmem: address of the working memory.
+ * This requires 'workmem' of LZ4_MEM_COMPRESS.
+ *
+ * Compresses 'sourceSize' bytes from buffer 'source'
+ * into already allocated 'dest' buffer of size 'maxOutputSize'.
+ * Compression is guaranteed to succeed if
+ * 'maxOutputSize' >= LZ4_compressBound(inputSize).
+ * It also runs faster, so it's a recommended setting.
+ * If the function cannot compress 'source' into a more limited 'dest' budget,
+ * compression stops *immediately*, and the function result is zero.
+ * As a consequence, 'dest' content is not valid.
+ *
+ * Return: Number of bytes written into buffer 'dest'
+ * (necessarily <= maxOutputSize) or 0 if compression fails
+ */
+int LZ4_compress_default(const char *source, char *dest, int inputSize,
+ int maxOutputSize, void *wrkmem);
+
+/**
+ * LZ4_compress_fast() - As LZ4_compress_default providing an acceleration param
+ * @source: source address of the original data
+ * @dest: output buffer address of the compressed data
+ * @inputSize: size of the input data. Max supported value is LZ4_MAX_INPUT_SIZE
+ * @maxOutputSize: full or partial size of buffer 'dest'
+ * which must be already allocated
+ * @acceleration: acceleration factor
+ * @wrkmem: address of the working memory.
+ * This requires 'workmem' of LZ4_MEM_COMPRESS.
+ *
+ * Same as LZ4_compress_default(), but allows to select an "acceleration"
+ * factor. The larger the acceleration value, the faster the algorithm,
+ * but also the lesser the compression. It's a trade-off. It can be fine tuned,
+ * with each successive value providing roughly +~3% to speed.
+ * An acceleration value of "1" is the same as regular LZ4_compress_default()
+ * Values <= 0 will be replaced by LZ4_ACCELERATION_DEFAULT, which is 1.
+ *
+ * Return: Number of bytes written into buffer 'dest'
+ * (necessarily <= maxOutputSize) or 0 if compression fails
+ */
+int LZ4_compress_fast(const char *source, char *dest, int inputSize,
+ int maxOutputSize, int acceleration, void *wrkmem);
+
+/**
+ * LZ4_compress_destSize() - Compress as much data as possible
+ * from source to dest
+ * @source: source address of the original data
+ * @dest: output buffer address of the compressed data
+ * @sourceSizePtr: will be modified to indicate how many bytes where read
+ * from 'source' to fill 'dest'. New value is necessarily <= old value.
+ * @targetDestSize: Size of buffer 'dest' which must be already allocated
+ * @wrkmem: address of the working memory.
+ * This requires 'workmem' of LZ4_MEM_COMPRESS.
+ *
+ * Reverse the logic, by compressing as much data as possible
+ * from 'source' buffer into already allocated buffer 'dest'
+ * of size 'targetDestSize'.
+ * This function either compresses the entire 'source' content into 'dest'
+ * if it's large enough, or fill 'dest' buffer completely with as much data as
+ * possible from 'source'.
+ *
+ * Return: Number of bytes written into 'dest' (necessarily <= targetDestSize)
+ * or 0 if compression fails
+ */
+int LZ4_compress_destSize(const char *source, char *dest, int *sourceSizePtr,
+ int targetDestSize, void *wrkmem);
/*
- * lz4_decompress()
- * src : source address of the compressed data
- * src_len : is the input size, whcih is returned after decompress done
- * dest : output buffer address of the decompressed data
- * actual_dest_len: is the size of uncompressed data, supposing it's known
- * return : Success if return 0
- * Error if return (< 0)
- * note : Destination buffer must be already allocated.
- * slightly faster than lz4_decompress_unknownoutputsize()
+ * lz4_compress() - For backward compatibility, see LZ4_compress_default
+ * @src: source address of the original data
+ * @src_len: size of the original data
+ * @dst: output buffer address of the compressed data. This requires 'dst'
+ * of size LZ4_COMPRESSBOUND
+ * @dst_len: is the output size, which is returned after compress done
+ * @workmem: address of the working memory.
+ *
+ * Return: Success if return 0, Error if return < 0
*/
-int lz4_decompress(const unsigned char *src, size_t *src_len,
- unsigned char *dest, size_t actual_dest_len);
+int lz4_compress(const unsigned char *src, size_t src_len, unsigned char *dst,
+ size_t *dst_len, void *wrkmem);
+
+/*-************************************************************************
+ * Decompression Functions
+ **************************************************************************/
+
+/**
+ * LZ4_decompress_fast() - Decompresses data from 'source' into 'dest'
+ * @source: source address of the compressed data
+ * @dest: output buffer address of the uncompressed data
+ * which must be already allocated with 'originalSize' bytes
+ * @originalSize: is the original and therefore uncompressed size
+ *
+ * Decompresses data from 'source' into 'dest'.
+ * This function fully respect memory boundaries for properly formed
+ * compressed data.
+ * It is a bit faster than LZ4_decompress_safe().
+ * However, it does not provide any protection against intentionally
+ * modified data stream (malicious input).
+ * Use this function in trusted environment only
+ * (data to decode comes from a trusted source).
+ *
+ * Return: number of bytes read from the source buffer
+ * or a negative result if decompression fails.
+ */
+int LZ4_decompress_fast(const char *source, char *dest, int originalSize);
+
+/**
+ * LZ4_decompress_safe() - Decompression protected against buffer overflow
+ * @source: source address of the compressed data
+ * @dest: output buffer address of the uncompressed data
+ * which must be already allocated
+ * @compressedSize: is the precise full size of the compressed block
+ * @maxDecompressedSize: is the size of 'dest' buffer
+ *
+ * Decompresses data fom 'source' into 'dest'.
+ * If the source stream is detected malformed, the function will
+ * stop decoding and return a negative result.
+ * This function is protected against buffer overflow exploits,
+ * including malicious data packets. It never writes outside output buffer,
+ * nor reads outside input buffer.
+ *
+ * Return: number of bytes decompressed into destination buffer
+ * (necessarily <= maxDecompressedSize)
+ * or a negative result in case of error
+ */
+int LZ4_decompress_safe(const char *source, char *dest, int compressedSize,
+ int maxDecompressedSize);
+
+/**
+ * LZ4_decompress_safe_partial() - Decompress a block of size 'compressedSize'
+ * at position 'source' into buffer 'dest'
+ * @source: source address of the compressed data
+ * @dest: output buffer address of the decompressed data which must be
+ * already allocated
+ * @compressedSize: is the precise full size of the compressed block.
+ * @targetOutputSize: the decompression operation will try
+ * to stop as soon as 'targetOutputSize' has been reached
+ * @maxDecompressedSize: is the size of destination buffer
+ *
+ * This function decompresses a compressed block of size 'compressedSize'
+ * at position 'source' into destination buffer 'dest'
+ * of size 'maxDecompressedSize'.
+ * The function tries to stop decompressing operation as soon as
+ * 'targetOutputSize' has been reached, reducing decompression time.
+ * This function never writes outside of output buffer,
+ * and never reads outside of input buffer.
+ * It is therefore protected against malicious data packets.
+ *
+ * Return: the number of bytes decoded in the destination buffer
+ * (necessarily <= maxDecompressedSize)
+ * or a negative result in case of error
+ *
+ */
+int LZ4_decompress_safe_partial(const char *source, char *dest,
+ int compressedSize, int targetOutputSize, int maxDecompressedSize);
/*
- * lz4_decompress_unknownoutputsize()
- * src : source address of the compressed data
- * src_len : is the input size, therefore the compressed size
- * dest : output buffer address of the decompressed data
- * dest_len: is the max size of the destination buffer, which is
- * returned with actual size of decompressed data after
- * decompress done
- * return : Success if return 0
- * Error if return (< 0)
- * note : Destination buffer must be already allocated.
+ * lz4_decompress_unknownoutputsize() - For backwards compatibility,
+ * see LZ4_decompress_safe
+ * @src: source address of the compressed data
+ * @src_len: is the input size, therefore the compressed size
+ * @dest: output buffer address of the decompressed data
+ * which must be already allocated
+ * @dest_len: is the max size of the destination buffer, which is
+ * returned with actual size of decompressed data after decompress done
+ *
+ * Return: Success if return 0, Error if return (< 0)
*/
int lz4_decompress_unknownoutputsize(const unsigned char *src, size_t src_len,
- unsigned char *dest, size_t *dest_len);
+ unsigned char *dest, size_t *dest_len);
+
+/**
+ * lz4_decompress() - For backwards cocmpatibility, see LZ4_decompress_fast
+ * @src: source address of the compressed data
+ * @src_len: is the input size, which is returned after decompress done
+ * @dest: output buffer address of the decompressed data,
+ * which must be already allocated
+ * @actual_dest_len: is the size of uncompressed data, supposing it's known
+ *
+ * Return: Success if return 0, Error if return (< 0)
+ */
+int lz4_decompress(const unsigned char *src, size_t *src_len,
+ unsigned char *dest, size_t actual_dest_len);
+
+/*-************************************************************************
+ * LZ4 HC Compression
+ **************************************************************************/
+
+/**
+ * LZ4_compress_HC() - Compress data from `src` into `dst`, using HC algorithm
+ * @src: source address of the original data
+ * @dst: output buffer address of the compressed data
+ * @srcSize: size of the input data. Max supported value is LZ4_MAX_INPUT_SIZE
+ * @dstCapacity: full or partial size of buffer 'dst',
+ * which must be already allocated
+ * @compressionLevel: Recommended values are between 4 and 9, although any
+ * value between 1 and LZ4HC_MAX_CLEVEL will work.
+ * Values >LZ4HC_MAX_CLEVEL behave the same as 16.
+ * @wrkmem: address of the working memory.
+ * This requires 'wrkmem' of size LZ4HC_MEM_COMPRESS.
+ *
+ * Compress data from 'src' into 'dst', using the more powerful
+ * but slower "HC" algorithm. Compression is guaranteed to succeed if
+ * `dstCapacity >= LZ4_compressBound(srcSize)
+ *
+ * Return : the number of bytes written into 'dst' or 0 if compression fails.
+ */
+int LZ4_compress_HC(const char *src, char *dst, int srcSize, int dstCapacity,
+ int compressionLevel, void *wrkmem);
+
+/**
+ * lz4hc_compress() - For backwards compatibility, see LZ4_compress_HC
+ * @src: source address of the original data
+ * @src_len: size of the original data
+ * @dst: output buffer address of the compressed data. This requires 'dst'
+ * of size LZ4_COMPRESSBOUND.
+ * @dst_len: is the output size, which is returned after compress done
+ * @wrkmem: address of the working memory.
+ * This requires 'workmem' of size LZ4HC_MEM_COMPRESS.
+ *
+ * Return : Success if return 0, Error if return (< 0)
+ */
+int lz4hc_compress(const unsigned char *src, size_t src_len, unsigned char *dst,
+ size_t *dst_len, void *wrkmem);
+
+/**
+ * LZ4_resetStreamHC() - Init an allocated 'LZ4_streamHC_t' structure
+ * @streamHCPtr: pointer to the 'LZ4_streamHC_t' structure
+ * @compressionLevel: Recommended values are between 4 and 9, although any
+ * value between 1 and LZ4HC_MAX_CLEVEL will work.
+ * Values >LZ4HC_MAX_CLEVEL behave the same as 16.
+ *
+ * An LZ4_streamHC_t structure can be allocated once
+ * and re-used multiple times.
+ * Use this function to init an allocated `LZ4_streamHC_t` structure
+ * and start a new compression.
+ */
+void LZ4_resetStreamHC(LZ4_streamHC_t *streamHCPtr, int compressionLevel);
+
+/**
+ * LZ4_loadDictHC() - Load a static dictionary into LZ4_streamHC
+ * @streamHCPtr: pointer to the LZ4HC_stream_t
+ * @dictionary: dictionary to load
+ * @dictSize: size of dictionary
+ *
+ * Use this function to load a static dictionary into LZ4HC_stream.
+ * Any previous data will be forgotten, only 'dictionary'
+ * will remain in memory.
+ * Loading a size of 0 is allowed.
+ *
+ * Return : dictionary size, in bytes (necessarily <= 64 KB)
+ */
+int LZ4_loadDictHC(LZ4_streamHC_t *streamHCPtr, const char *dictionary,
+ int dictSize);
+
+/**
+ * LZ4_compress_HC_continue() - Compress 'src' using data from previously
+ * compressed blocks as a dictionary using the HC algorithm
+ * @streamHCPtr: Pointer to the previous 'LZ4_streamHC_t' structure
+ * @src: source address of the original data
+ * @dst: output buffer address of the compressed data,
+ * which must be already allocated
+ * @srcSize: size of the input data. Max supported value is LZ4_MAX_INPUT_SIZE
+ * @maxDstSize: full or partial size of buffer 'dest'
+ * which must be already allocated
+ *
+ * These functions compress data in successive blocks of any size, using
+ * previous blocks as dictionary. One key assumption is that previous
+ * blocks (up to 64 KB) remain read-accessible while
+ * compressing next blocks. There is an exception for ring buffers,
+ * which can be smaller than 64 KB.
+ * Ring buffers scenario is automatically detected and handled by
+ * LZ4_compress_HC_continue().
+ * Before starting compression, state must be properly initialized,
+ * using LZ4_resetStreamHC().
+ * A first "fictional block" can then be designated as
+ * initial dictionary, using LZ4_loadDictHC() (Optional).
+ * Then, use LZ4_compress_HC_continue()
+ * to compress each successive block. Previous memory blocks
+ * (including initial dictionary when present) must remain accessible
+ * and unmodified during compression.
+ * 'dst' buffer should be sized to handle worst case scenarios, using
+ * LZ4_compressBound(), to ensure operation success.
+ * If, for any reason, previous data blocks can't be preserved unmodified
+ * in memory during next compression block,
+ * you must save it to a safer memory space, using LZ4_saveDictHC().
+ * Return value of LZ4_saveDictHC() is the size of dictionary
+ * effectively saved into 'safeBuffer'.
+ *
+ * Return: Number of bytes written into buffer 'dst' or 0 if compression fails
+ */
+int LZ4_compress_HC_continue(LZ4_streamHC_t *streamHCPtr, const char *src,
+ char *dst, int srcSize, int maxDstSize);
+
+/**
+ * LZ4_saveDictHC() - Save static dictionary from LZ4HC_stream
+ * @streamHCPtr: pointer to the 'LZ4HC_stream_t' structure
+ * @safeBuffer: buffer to save dictionary to, must be already allocated
+ * @maxDictSize: size of 'safeBuffer'
+ *
+ * If previously compressed data block is not guaranteed
+ * to remain available at its memory location,
+ * save it into a safer place (char *safeBuffer).
+ * Note : you don't need to call LZ4_loadDictHC() afterwards,
+ * dictionary is immediately usable, you can therefore call
+ * LZ4_compress_HC_continue().
+ *
+ * Return : saved dictionary size in bytes (necessarily <= maxDictSize),
+ * or 0 if error.
+ */
+int LZ4_saveDictHC(LZ4_streamHC_t *streamHCPtr, char *safeBuffer,
+ int maxDictSize);
+
+/*-*********************************************
+ * Streaming Compression Functions
+ ***********************************************/
+
+/**
+ * LZ4_resetStream() - Init an allocated 'LZ4_stream_t' structure
+ * @LZ4_stream: pointer to the 'LZ4_stream_t' structure
+ *
+ * An LZ4_stream_t structure can be allocated once
+ * and re-used multiple times.
+ * Use this function to init an allocated `LZ4_stream_t` structure
+ * and start a new compression.
+ */
+void LZ4_resetStream(LZ4_stream_t *LZ4_stream);
+
+/**
+ * LZ4_loadDict() - Load a static dictionary into LZ4_stream
+ * @streamPtr: pointer to the LZ4_stream_t
+ * @dictionary: dictionary to load
+ * @dictSize: size of dictionary
+ *
+ * Use this function to load a static dictionary into LZ4_stream.
+ * Any previous data will be forgotten, only 'dictionary'
+ * will remain in memory.
+ * Loading a size of 0 is allowed.
+ *
+ * Return : dictionary size, in bytes (necessarily <= 64 KB)
+ */
+int LZ4_loadDict(LZ4_stream_t *streamPtr, const char *dictionary,
+ int dictSize);
+
+/**
+ * LZ4_saveDict() - Save static dictionary from LZ4_stream
+ * @streamPtr: pointer to the 'LZ4_stream_t' structure
+ * @safeBuffer: buffer to save dictionary to, must be already allocated
+ * @dictSize: size of 'safeBuffer'
+ *
+ * If previously compressed data block is not guaranteed
+ * to remain available at its memory location,
+ * save it into a safer place (char *safeBuffer).
+ * Note : you don't need to call LZ4_loadDict() afterwards,
+ * dictionary is immediately usable, you can therefore call
+ * LZ4_compress_fast_continue().
+ *
+ * Return : saved dictionary size in bytes (necessarily <= dictSize),
+ * or 0 if error.
+ */
+int LZ4_saveDict(LZ4_stream_t *streamPtr, char *safeBuffer, int dictSize);
+
+/**
+ * LZ4_compress_fast_continue() - Compress 'src' using data from previously
+ * compressed blocks as a dictionary
+ * @streamPtr: Pointer to the previous 'LZ4_stream_t' structure
+ * @src: source address of the original data
+ * @dst: output buffer address of the compressed data,
+ * which must be already allocated
+ * @srcSize: size of the input data. Max supported value is LZ4_MAX_INPUT_SIZE
+ * @maxDstSize: full or partial size of buffer 'dest'
+ * which must be already allocated
+ * @acceleration: acceleration factor
+ *
+ * Compress buffer content 'src', using data from previously compressed blocks
+ * as dictionary to improve compression ratio.
+ * Important : Previous data blocks are assumed to still
+ * be present and unmodified !
+ * If maxDstSize >= LZ4_compressBound(srcSize),
+ * compression is guaranteed to succeed, and runs faster.
+ *
+ * Return: Number of bytes written into buffer 'dst' or 0 if compression fails
+ */
+int LZ4_compress_fast_continue(LZ4_stream_t *streamPtr, const char *src,
+ char *dst, int srcSize, int maxDstSize, int acceleration);
+
+/**
+ * LZ4_setStreamDecode() - Instruct where to find dictionary
+ * @LZ4_streamDecode: the 'LZ4_streamDecode_t' structure
+ * @dictionary: dictionary to use
+ * @dictSize: size of dictionary
+ *
+ * Use this function to instruct where to find the dictionary.
+ * Setting a size of 0 is allowed (same effect as reset).
+ *
+ * Return: 1 if OK, 0 if error
+ */
+int LZ4_setStreamDecode(LZ4_streamDecode_t *LZ4_streamDecode,
+ const char *dictionary, int dictSize);
+
+/**
+ * LZ4_decompress_fast_continue() - Decompress blocks in streaming mode
+ * @LZ4_streamDecode: the 'LZ4_streamDecode_t' structure
+ * @source: source address of the compressed data
+ * @dest: output buffer address of the uncompressed data
+ * which must be already allocated
+ * @compressedSize: is the precise full size of the compressed block
+ * @maxDecompressedSize: is the size of 'dest' buffer
+ *
+ * These decoding function allows decompression of multiple blocks
+ * in "streaming" mode.
+ * Previously decoded blocks *must* remain available at the memory position
+ * where they were decoded (up to 64 KB)
+ * In the case of a ring buffers, decoding buffer must be either :
+ * - Exactly same size as encoding buffer, with same update rule
+ * (block boundaries at same positions) In which case,
+ * the decoding & encoding ring buffer can have any size,
+ * including very small ones ( < 64 KB).
+ * - Larger than encoding buffer, by a minimum of maxBlockSize more bytes.
+ * maxBlockSize is implementation dependent.
+ * It's the maximum size you intend to compress into a single block.
+ * In which case, encoding and decoding buffers do not need
+ * to be synchronized, and encoding ring buffer can have any size,
+ * including small ones ( < 64 KB).
+ * - _At least_ 64 KB + 8 bytes + maxBlockSize.
+ * In which case, encoding and decoding buffers do not need to be
+ * synchronized, and encoding ring buffer can have any size,
+ * including larger than decoding buffer. W
+ * Whenever these conditions are not possible, save the last 64KB of decoded
+ * data into a safe buffer, and indicate where it is saved
+ * using LZ4_setStreamDecode()
+ *
+ * Return: number of bytes decompressed into destination buffer
+ * (necessarily <= maxDecompressedSize)
+ * or a negative result in case of error
+ */
+int LZ4_decompress_safe_continue(LZ4_streamDecode_t *LZ4_streamDecode,
+ const char *source, char *dest, int compressedSize,
+ int maxDecompressedSize);
+
+/**
+ * LZ4_decompress_fast_continue() - Decompress blocks in streaming mode
+ * @LZ4_streamDecode: the 'LZ4_streamDecode_t' structure
+ * @source: source address of the compressed data
+ * @dest: output buffer address of the uncompressed data
+ * which must be already allocated with 'originalSize' bytes
+ * @originalSize: is the original and therefore uncompressed size
+ *
+ * These decoding function allows decompression of multiple blocks
+ * in "streaming" mode.
+ * Previously decoded blocks *must* remain available at the memory position
+ * where they were decoded (up to 64 KB)
+ * In the case of a ring buffers, decoding buffer must be either :
+ * - Exactly same size as encoding buffer, with same update rule
+ * (block boundaries at same positions) In which case,
+ * the decoding & encoding ring buffer can have any size,
+ * including very small ones ( < 64 KB).
+ * - Larger than encoding buffer, by a minimum of maxBlockSize more bytes.
+ * maxBlockSize is implementation dependent.
+ * It's the maximum size you intend to compress into a single block.
+ * In which case, encoding and decoding buffers do not need
+ * to be synchronized, and encoding ring buffer can have any size,
+ * including small ones ( < 64 KB).
+ * - _At least_ 64 KB + 8 bytes + maxBlockSize.
+ * In which case, encoding and decoding buffers do not need to be
+ * synchronized, and encoding ring buffer can have any size,
+ * including larger than decoding buffer. W
+ * Whenever these conditions are not possible, save the last 64KB of decoded
+ * data into a safe buffer, and indicate where it is saved
+ * using LZ4_setStreamDecode()
+ *
+ * Return: number of bytes decompressed into destination buffer
+ * (necessarily <= maxDecompressedSize)
+ * or a negative result in case of error
+ */
+int LZ4_decompress_fast_continue(LZ4_streamDecode_t *LZ4_streamDecode,
+ const char *source, char *dest, int originalSize);
+
+/**
+ * LZ4_decompress_safe_usingDict() - Same as LZ4_setStreamDecode()
+ * followed by LZ4_decompress_safe_continue()
+ * @source: source address of the compressed data
+ * @dest: output buffer address of the uncompressed data
+ * which must be already allocated
+ * @compressedSize: is the precise full size of the compressed block
+ * @maxDecompressedSize: is the size of 'dest' buffer
+ * @dictStart: pointer to the start of the dictionary in memory
+ * @dictSize: size of dictionary
+ *
+ * These decoding function works the same as
+ * a combination of LZ4_setStreamDecode() followed by
+ * LZ4_decompress_safe_continue()
+ * It is stand-alone, and don'tn eed a LZ4_streamDecode_t structure.
+ *
+ * Return: number of bytes decompressed into destination buffer
+ * (necessarily <= maxDecompressedSize)
+ * or a negative result in case of error
+ */
+int LZ4_decompress_safe_usingDict(const char *source, char *dest,
+ int compressedSize, int maxDecompressedSize, const char *dictStart,
+ int dictSize);
+
+/**
+ * LZ4_decompress_fast_usingDict() - Same as LZ4_setStreamDecode()
+ * followed by LZ4_decompress_fast_continue()
+ * @source: source address of the compressed data
+ * @dest: output buffer address of the uncompressed data
+ * which must be already allocated with 'originalSize' bytes
+ * @originalSize: is the original and therefore uncompressed size
+ * @dictStart: pointer to the start of the dictionary in memory
+ * @dictSize: size of dictionary
+ *
+ * These decoding function works the same as
+ * a combination of LZ4_setStreamDecode() followed by
+ * LZ4_decompress_safe_continue()
+ * It is stand-alone, and don'tn eed a LZ4_streamDecode_t structure.
+ *
+ * Return: number of bytes decompressed into destination buffer
+ * (necessarily <= maxDecompressedSize)
+ * or a negative result in case of error
+ */
+int LZ4_decompress_fast_usingDict(const char *source, char *dest,
+ int originalSize, const char *dictStart, int dictSize);
+
#endif
diff --git a/lib/lz4/Makefile b/lib/lz4/Makefile
index 8085d04e9309..f7b113271d13 100644
--- a/lib/lz4/Makefile
+++ b/lib/lz4/Makefile
@@ -1,3 +1,5 @@
+ccflags-y += -O3
+
obj-$(CONFIG_LZ4_COMPRESS) += lz4_compress.o
obj-$(CONFIG_LZ4HC_COMPRESS) += lz4hc_compress.o
obj-$(CONFIG_LZ4_DECOMPRESS) += lz4_decompress.o
diff --git a/lib/lz4/lz4_compress.c b/lib/lz4/lz4_compress.c
index 28321d8f75ef..53f313f05185 100644
--- a/lib/lz4/lz4_compress.c
+++ b/lib/lz4/lz4_compress.c
@@ -1,19 +1,16 @@
/*
* LZ4 - Fast LZ compression algorithm
- * Copyright (C) 2011-2012, Yann Collet.
- * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
-
+ * Copyright (C) 2011 - 2016, Yann Collet.
+ * BSD 2 - Clause License (http://www.opensource.org/licenses/bsd - license.php)
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
- *
- * * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * * Redistributions in binary form must reproduce the above
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
- *
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
@@ -25,417 +22,939 @@
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- *
* You can contact the author at :
- * - LZ4 homepage : http://fastcompression.blogspot.com/p/lz4.html
- * - LZ4 source repository : http://code.google.com/p/lz4/
+ * - LZ4 homepage : http://www.lz4.org
+ * - LZ4 source repository : https://github.com/lz4/lz4
*
- * Changed for kernel use by:
- * Chanho Min <chanho.min@lge.com>
+ * Changed for kernel usage by:
+ * Sven Schmidt <4sschmid@informatik.uni-hamburg.de>
*/
+/*-************************************
+ * Dependencies
+ **************************************/
+#include <linux/lz4.h>
+#include "lz4defs.h"
#include <linux/module.h>
#include <linux/kernel.h>
-#include <linux/lz4.h>
#include <asm/unaligned.h>
-#include "lz4defs.h"
-/*
- * LZ4_compressCtx :
- * -----------------
- * Compress 'isize' bytes from 'source' into an output buffer 'dest' of
- * maximum size 'maxOutputSize'. * If it cannot achieve it, compression
- * will stop, and result of the function will be zero.
- * return : the number of bytes written in buffer 'dest', or 0 if the
- * compression fails
- */
-static inline int lz4_compressctx(void *ctx,
- const char *source,
- char *dest,
- int isize,
- int maxoutputsize)
+static const int LZ4_minLength = (MFLIMIT + 1);
+static const int LZ4_64Klimit = ((64 * KB) + (MFLIMIT - 1));
+
+/*-******************************
+ * Compression functions
+ ********************************/
+static FORCE_INLINE U32 LZ4_hash4(
+ U32 sequence,
+ tableType_t const tableType)
{
- HTYPE *hashtable = (HTYPE *)ctx;
- const u8 *ip = (u8 *)source;
-#if LZ4_ARCH64
- const BYTE * const base = ip;
+ if (tableType == byU16)
+ return ((sequence * 2654435761U)
+ >> ((MINMATCH * 8) - (LZ4_HASHLOG + 1)));
+ else
+ return ((sequence * 2654435761U)
+ >> ((MINMATCH * 8) - LZ4_HASHLOG));
+}
+
+static FORCE_INLINE U32 LZ4_hash5(
+ U64 sequence,
+ tableType_t const tableType)
+{
+ const U32 hashLog = (tableType == byU16)
+ ? LZ4_HASHLOG + 1
+ : LZ4_HASHLOG;
+
+#if LZ4_LITTLE_ENDIAN
+ static const U64 prime5bytes = 889523592379ULL;
+
+ return (U32)(((sequence << 24) * prime5bytes) >> (64 - hashLog));
#else
- const int base = 0;
+ static const U64 prime8bytes = 11400714785074694791ULL;
+
+ return (U32)(((sequence >> 24) * prime8bytes) >> (64 - hashLog));
#endif
- const u8 *anchor = ip;
- const u8 *const iend = ip + isize;
- const u8 *const mflimit = iend - MFLIMIT;
- #define MATCHLIMIT (iend - LASTLITERALS)
-
- u8 *op = (u8 *) dest;
- u8 *const oend = op + maxoutputsize;
- int length;
- const int skipstrength = SKIPSTRENGTH;
- u32 forwardh;
- int lastrun;
-
- /* Init */
- if (isize < MINLENGTH)
- goto _last_literals;
+}
+
+static FORCE_INLINE U32 LZ4_hashPosition(
+ const void *p,
+ tableType_t const tableType)
+{
+#if LZ4_ARCH64
+ if (tableType == byU32)
+ return LZ4_hash5(LZ4_read_ARCH(p), tableType);
+#endif
+
+ return LZ4_hash4(LZ4_read32(p), tableType);
+}
+
+static void LZ4_putPositionOnHash(
+ const BYTE *p,
+ U32 h,
+ void *tableBase,
+ tableType_t const tableType,
+ const BYTE *srcBase)
+{
+ switch (tableType) {
+ case byPtr:
+ {
+ const BYTE **hashTable = (const BYTE **)tableBase;
+
+ hashTable[h] = p;
+ return;
+ }
+ case byU32:
+ {
+ U32 *hashTable = (U32 *) tableBase;
+
+ hashTable[h] = (U32)(p - srcBase);
+ return;
+ }
+ case byU16:
+ {
+ U16 *hashTable = (U16 *) tableBase;
+
+ hashTable[h] = (U16)(p - srcBase);
+ return;
+ }
+ }
+}
+
+static FORCE_INLINE void LZ4_putPosition(
+ const BYTE *p,
+ void *tableBase,
+ tableType_t tableType,
+ const BYTE *srcBase)
+{
+ U32 const h = LZ4_hashPosition(p, tableType);
+
+ LZ4_putPositionOnHash(p, h, tableBase, tableType, srcBase);
+}
+
+static const BYTE *LZ4_getPositionOnHash(
+ U32 h,
+ void *tableBase,
+ tableType_t tableType,
+ const BYTE *srcBase)
+{
+ if (tableType == byPtr) {
+ const BYTE **hashTable = (const BYTE **) tableBase;
+
+ return hashTable[h];
+ }
+
+ if (tableType == byU32) {
+ const U32 * const hashTable = (U32 *) tableBase;
+
+ return hashTable[h] + srcBase;
+ }
+
+ {
+ /* default, to ensure a return */
+ const U16 * const hashTable = (U16 *) tableBase;
+
+ return hashTable[h] + srcBase;
+ }
+}
+
+static FORCE_INLINE const BYTE *LZ4_getPosition(
+ const BYTE *p,
+ void *tableBase,
+ tableType_t tableType,
+ const BYTE *srcBase)
+{
+ U32 const h = LZ4_hashPosition(p, tableType);
+
+ return LZ4_getPositionOnHash(h, tableBase, tableType, srcBase);
+}
+
- memset((void *)hashtable, 0, LZ4_MEM_COMPRESS);
+/*
+ * LZ4_compress_generic() :
+ * inlined, to ensure branches are decided at compilation time
+ */
+static FORCE_INLINE int LZ4_compress_generic(
+ LZ4_stream_t_internal * const dictPtr,
+ const char * const source,
+ char * const dest,
+ const int inputSize,
+ const int maxOutputSize,
+ const limitedOutput_directive outputLimited,
+ const tableType_t tableType,
+ const dict_directive dict,
+ const dictIssue_directive dictIssue,
+ const U32 acceleration)
+{
+ const BYTE *ip = (const BYTE *) source;
+ const BYTE *base;
+ const BYTE *lowLimit;
+ const BYTE * const lowRefLimit = ip - dictPtr->dictSize;
+ const BYTE * const dictionary = dictPtr->dictionary;
+ const BYTE * const dictEnd = dictionary + dictPtr->dictSize;
+ const size_t dictDelta = dictEnd - (const BYTE *)source;
+ const BYTE *anchor = (const BYTE *) source;
+ const BYTE * const iend = ip + inputSize;
+ const BYTE * const mflimit = iend - MFLIMIT;
+ const BYTE * const matchlimit = iend - LASTLITERALS;
+
+ BYTE *op = (BYTE *) dest;
+ BYTE * const olimit = op + maxOutputSize;
+
+ U32 forwardH;
+ size_t refDelta = 0;
+
+ /* Init conditions */
+ if ((U32)inputSize > (U32)LZ4_MAX_INPUT_SIZE) {
+ /* Unsupported inputSize, too large (or negative) */
+ return 0;
+ }
+
+ switch (dict) {
+ case noDict:
+ default:
+ base = (const BYTE *)source;
+ lowLimit = (const BYTE *)source;
+ break;
+ case withPrefix64k:
+ base = (const BYTE *)source - dictPtr->currentOffset;
+ lowLimit = (const BYTE *)source - dictPtr->dictSize;
+ break;
+ case usingExtDict:
+ base = (const BYTE *)source - dictPtr->currentOffset;
+ lowLimit = (const BYTE *)source;
+ break;
+ }
+
+ if ((tableType == byU16)
+ && (inputSize >= LZ4_64Klimit)) {
+ /* Size too large (not within 64K limit) */
+ return 0;
+ }
+
+ if (inputSize < LZ4_minLength) {
+ /* Input too small, no compression (all literals) */
+ goto _last_literals;
+ }
/* First Byte */
- hashtable[LZ4_HASH_VALUE(ip)] = ip - base;
+ LZ4_putPosition(ip, dictPtr->hashTable, tableType, base);
ip++;
- forwardh = LZ4_HASH_VALUE(ip);
+ forwardH = LZ4_hashPosition(ip, tableType);
/* Main Loop */
- for (;;) {
- int findmatchattempts = (1U << skipstrength) + 3;
- const u8 *forwardip = ip;
- const u8 *ref;
- u8 *token;
+ for ( ; ; ) {
+ const BYTE *match;
+ BYTE *token;
/* Find a match */
- do {
- u32 h = forwardh;
- int step = findmatchattempts++ >> skipstrength;
- ip = forwardip;
- forwardip = ip + step;
-
- if (unlikely(forwardip > mflimit))
- goto _last_literals;
-
- forwardh = LZ4_HASH_VALUE(forwardip);
- ref = base + hashtable[h];
- hashtable[h] = ip - base;
- } while ((ref < ip - MAX_DISTANCE) || (A32(ref) != A32(ip)));
+ {
+ const BYTE *forwardIp = ip;
+ unsigned int step = 1;
+ unsigned int searchMatchNb = acceleration << LZ4_SKIPTRIGGER;
+
+ do {
+ U32 const h = forwardH;
+
+ ip = forwardIp;
+ forwardIp += step;
+ step = (searchMatchNb++ >> LZ4_SKIPTRIGGER);
+
+ if (unlikely(forwardIp > mflimit))
+ goto _last_literals;
+
+ match = LZ4_getPositionOnHash(h,
+ dictPtr->hashTable,
+ tableType, base);
+
+ if (dict == usingExtDict) {
+ if (match < (const BYTE *)source) {
+ refDelta = dictDelta;
+ lowLimit = dictionary;
+ } else {
+ refDelta = 0;
+ lowLimit = (const BYTE *)source;
+ } }
+
+ forwardH = LZ4_hashPosition(forwardIp,
+ tableType);
+
+ LZ4_putPositionOnHash(ip, h, dictPtr->hashTable,
+ tableType, base);
+ } while (((dictIssue == dictSmall)
+ ? (match < lowRefLimit)
+ : 0)
+ || ((tableType == byU16)
+ ? 0
+ : (match + MAX_DISTANCE < ip))
+ || (LZ4_read32(match + refDelta)
+ != LZ4_read32(ip)));
+ }
/* Catch up */
- while ((ip > anchor) && (ref > (u8 *)source) &&
- unlikely(ip[-1] == ref[-1])) {
+ while (((ip > anchor) & (match + refDelta > lowLimit))
+ && (unlikely(ip[-1] == match[refDelta - 1]))) {
ip--;
- ref--;
+ match--;
}
- /* Encode Literal length */
- length = (int)(ip - anchor);
- token = op++;
- /* check output limit */
- if (unlikely(op + length + (2 + 1 + LASTLITERALS) +
- (length >> 8) > oend))
- return 0;
+ /* Encode Literals */
+ {
+ unsigned const int litLength = (unsigned int)(ip - anchor);
- if (length >= (int)RUN_MASK) {
- int len;
- *token = (RUN_MASK << ML_BITS);
- len = length - RUN_MASK;
- for (; len > 254 ; len -= 255)
- *op++ = 255;
- *op++ = (u8)len;
- } else
- *token = (length << ML_BITS);
+ token = op++;
+
+ if ((outputLimited) &&
+ /* Check output buffer overflow */
+ (unlikely(op + litLength +
+ (2 + 1 + LASTLITERALS) +
+ (litLength / 255) > olimit)))
+ return 0;
+
+ if (litLength >= RUN_MASK) {
+ int len = (int)litLength - RUN_MASK;
+
+ *token = (RUN_MASK << ML_BITS);
+
+ for (; len >= 255; len -= 255)
+ *op++ = 255;
+ *op++ = (BYTE)len;
+ } else
+ *token = (BYTE)(litLength << ML_BITS);
+
+ /* Copy Literals */
+ LZ4_wildCopy(op, anchor, op + litLength);
+ op += litLength;
+ }
- /* Copy Literals */
- LZ4_BLINDCOPY(anchor, op, length);
_next_match:
/* Encode Offset */
- LZ4_WRITE_LITTLEENDIAN_16(op, (u16)(ip - ref));
+ LZ4_writeLE16(op, (U16)(ip - match));
+ op += 2;
- /* Start Counting */
- ip += MINMATCH;
- /* MinMatch verified */
- ref += MINMATCH;
- anchor = ip;
- while (likely(ip < MATCHLIMIT - (STEPSIZE - 1))) {
- #if LZ4_ARCH64
- u64 diff = A64(ref) ^ A64(ip);
- #else
- u32 diff = A32(ref) ^ A32(ip);
- #endif
- if (!diff) {
- ip += STEPSIZE;
- ref += STEPSIZE;
- continue;
- }
- ip += LZ4_NBCOMMONBYTES(diff);
- goto _endcount;
- }
- #if LZ4_ARCH64
- if ((ip < (MATCHLIMIT - 3)) && (A32(ref) == A32(ip))) {
- ip += 4;
- ref += 4;
- }
- #endif
- if ((ip < (MATCHLIMIT - 1)) && (A16(ref) == A16(ip))) {
- ip += 2;
- ref += 2;
- }
- if ((ip < MATCHLIMIT) && (*ref == *ip))
- ip++;
-_endcount:
/* Encode MatchLength */
- length = (int)(ip - anchor);
- /* Check output limit */
- if (unlikely(op + (1 + LASTLITERALS) + (length >> 8) > oend))
- return 0;
- if (length >= (int)ML_MASK) {
- *token += ML_MASK;
- length -= ML_MASK;
- for (; length > 509 ; length -= 510) {
- *op++ = 255;
- *op++ = 255;
- }
- if (length > 254) {
- length -= 255;
- *op++ = 255;
+ {
+ unsigned int matchCode;
+
+ if ((dict == usingExtDict)
+ && (lowLimit == dictionary)) {
+ const BYTE *limit;
+
+ match += refDelta;
+ limit = ip + (dictEnd - match);
+
+ if (limit > matchlimit)
+ limit = matchlimit;
+
+ matchCode = LZ4_count(ip + MINMATCH,
+ match + MINMATCH, limit);
+
+ ip += MINMATCH + matchCode;
+
+ if (ip == limit) {
+ unsigned const int more = LZ4_count(ip,
+ (const BYTE *)source,
+ matchlimit);
+
+ matchCode += more;
+ ip += more;
+ }
+ } else {
+ matchCode = LZ4_count(ip + MINMATCH,
+ match + MINMATCH, matchlimit);
+ ip += MINMATCH + matchCode;
}
- *op++ = (u8)length;
- } else
- *token += length;
+
+ if (outputLimited &&
+ /* Check output buffer overflow */
+ (unlikely(op +
+ (1 + LASTLITERALS) +
+ (matchCode >> 8) > olimit)))
+ return 0;
+
+ if (matchCode >= ML_MASK) {
+ *token += ML_MASK;
+ matchCode -= ML_MASK;
+ LZ4_write32(op, 0xFFFFFFFF);
+
+ while (matchCode >= 4 * 255) {
+ op += 4;
+ LZ4_write32(op, 0xFFFFFFFF);
+ matchCode -= 4 * 255;
+ }
+
+ op += matchCode / 255;
+ *op++ = (BYTE)(matchCode % 255);
+ } else
+ *token += (BYTE)(matchCode);
+ }
+
+ anchor = ip;
/* Test end of chunk */
- if (ip > mflimit) {
- anchor = ip;
+ if (ip > mflimit)
break;
- }
/* Fill table */
- hashtable[LZ4_HASH_VALUE(ip-2)] = ip - 2 - base;
+ LZ4_putPosition(ip - 2, dictPtr->hashTable, tableType, base);
/* Test next position */
- ref = base + hashtable[LZ4_HASH_VALUE(ip)];
- hashtable[LZ4_HASH_VALUE(ip)] = ip - base;
- if ((ref > ip - (MAX_DISTANCE + 1)) && (A32(ref) == A32(ip))) {
+ match = LZ4_getPosition(ip, dictPtr->hashTable,
+ tableType, base);
+
+ if (dict == usingExtDict) {
+ if (match < (const BYTE *)source) {
+ refDelta = dictDelta;
+ lowLimit = dictionary;
+ } else {
+ refDelta = 0;
+ lowLimit = (const BYTE *)source;
+ }
+ }
+
+ LZ4_putPosition(ip, dictPtr->hashTable, tableType, base);
+
+ if (((dictIssue == dictSmall) ? (match >= lowRefLimit) : 1)
+ && (match + MAX_DISTANCE >= ip)
+ && (LZ4_read32(match + refDelta) == LZ4_read32(ip))) {
token = op++;
*token = 0;
goto _next_match;
}
/* Prepare next loop */
- anchor = ip++;
- forwardh = LZ4_HASH_VALUE(ip);
+ forwardH = LZ4_hashPosition(++ip, tableType);
}
_last_literals:
/* Encode Last Literals */
- lastrun = (int)(iend - anchor);
- if (((char *)op - dest) + lastrun + 1
- + ((lastrun + 255 - RUN_MASK) / 255) > (u32)maxoutputsize)
- return 0;
+ {
+ size_t const lastRun = (size_t)(iend - anchor);
- if (lastrun >= (int)RUN_MASK) {
- *op++ = (RUN_MASK << ML_BITS);
- lastrun -= RUN_MASK;
- for (; lastrun > 254 ; lastrun -= 255)
- *op++ = 255;
- *op++ = (u8)lastrun;
- } else
- *op++ = (lastrun << ML_BITS);
- memcpy(op, anchor, iend - anchor);
- op += iend - anchor;
+ if ((outputLimited) &&
+ /* Check output buffer overflow */
+ ((op - (BYTE *)dest) + lastRun + 1 +
+ ((lastRun + 255 - RUN_MASK) / 255) > (U32)maxOutputSize))
+ return 0;
+
+ if (lastRun >= RUN_MASK) {
+ size_t accumulator = lastRun - RUN_MASK;
+ *op++ = RUN_MASK << ML_BITS;
+ for (; accumulator >= 255; accumulator -= 255)
+ *op++ = 255;
+ *op++ = (BYTE) accumulator;
+ } else {
+ *op++ = (BYTE)(lastRun << ML_BITS);
+ }
+
+ memcpy(op, anchor, lastRun);
+
+ op += lastRun;
+ }
/* End */
- return (int)(((char *)op) - dest);
+ return (int) (((char *)op) - dest);
}
-static inline int lz4_compress64kctx(void *ctx,
- const char *source,
- char *dest,
- int isize,
- int maxoutputsize)
+static int LZ4_compress_fast_extState(
+ void *state,
+ const char *source,
+ char *dest,
+ int inputSize,
+ int maxOutputSize,
+ int acceleration)
{
- u16 *hashtable = (u16 *)ctx;
- const u8 *ip = (u8 *) source;
- const u8 *anchor = ip;
- const u8 *const base = ip;
- const u8 *const iend = ip + isize;
- const u8 *const mflimit = iend - MFLIMIT;
- #define MATCHLIMIT (iend - LASTLITERALS)
-
- u8 *op = (u8 *) dest;
- u8 *const oend = op + maxoutputsize;
- int len, length;
- const int skipstrength = SKIPSTRENGTH;
- u32 forwardh;
- int lastrun;
-
- /* Init */
- if (isize < MINLENGTH)
- goto _last_literals;
+ LZ4_stream_t_internal *ctx = &((LZ4_stream_t *)state)->internal_donotuse;
+#if LZ4_ARCH64
+ const tableType_t tableType = byU32;
+#else
+ const tableType_t tableType = byPtr;
+#endif
- memset((void *)hashtable, 0, LZ4_MEM_COMPRESS);
+ LZ4_resetStream((LZ4_stream_t *)state);
+
+ if (acceleration < 1)
+ acceleration = LZ4_ACCELERATION_DEFAULT;
+
+ if (maxOutputSize >= LZ4_COMPRESSBOUND(inputSize)) {
+ if (inputSize < LZ4_64Klimit)
+ return LZ4_compress_generic(ctx, source,
+ dest, inputSize, 0,
+ noLimit, byU16, noDict,
+ noDictIssue, acceleration);
+ else
+ return LZ4_compress_generic(ctx, source,
+ dest, inputSize, 0,
+ noLimit, tableType, noDict,
+ noDictIssue, acceleration);
+ } else {
+ if (inputSize < LZ4_64Klimit)
+ return LZ4_compress_generic(ctx, source,
+ dest, inputSize,
+ maxOutputSize, limitedOutput, byU16, noDict,
+ noDictIssue, acceleration);
+ else
+ return LZ4_compress_generic(ctx, source,
+ dest, inputSize,
+ maxOutputSize, limitedOutput, tableType, noDict,
+ noDictIssue, acceleration);
+ }
+}
+
+int LZ4_compress_fast(const char *source, char *dest, int inputSize,
+ int maxOutputSize, int acceleration, void *wrkmem)
+{
+ return LZ4_compress_fast_extState(wrkmem, source, dest, inputSize,
+ maxOutputSize, acceleration);
+}
+EXPORT_SYMBOL(LZ4_compress_fast);
+
+int LZ4_compress_default(const char *source, char *dest, int inputSize,
+ int maxOutputSize, void *wrkmem)
+{
+ return LZ4_compress_fast(source, dest, inputSize,
+ maxOutputSize, LZ4_ACCELERATION_DEFAULT, wrkmem);
+}
+EXPORT_SYMBOL(LZ4_compress_default);
+
+/*-******************************
+ * *_destSize() variant
+ ********************************/
+static int LZ4_compress_destSize_generic(
+ LZ4_stream_t_internal * const ctx,
+ const char * const src,
+ char * const dst,
+ int * const srcSizePtr,
+ const int targetDstSize,
+ const tableType_t tableType)
+{
+ const BYTE *ip = (const BYTE *) src;
+ const BYTE *base = (const BYTE *) src;
+ const BYTE *lowLimit = (const BYTE *) src;
+ const BYTE *anchor = ip;
+ const BYTE * const iend = ip + *srcSizePtr;
+ const BYTE * const mflimit = iend - MFLIMIT;
+ const BYTE * const matchlimit = iend - LASTLITERALS;
+
+ BYTE *op = (BYTE *) dst;
+ BYTE * const oend = op + targetDstSize;
+ BYTE * const oMaxLit = op + targetDstSize - 2 /* offset */
+ - 8 /* because 8 + MINMATCH == MFLIMIT */ - 1 /* token */;
+ BYTE * const oMaxMatch = op + targetDstSize
+ - (LASTLITERALS + 1 /* token */);
+ BYTE * const oMaxSeq = oMaxLit - 1 /* token */;
+
+ U32 forwardH;
+
+ /* Init conditions */
+ /* Impossible to store anything */
+ if (targetDstSize < 1)
+ return 0;
+ /* Unsupported input size, too large (or negative) */
+ if ((U32)*srcSizePtr > (U32)LZ4_MAX_INPUT_SIZE)
+ return 0;
+ /* Size too large (not within 64K limit) */
+ if ((tableType == byU16) && (*srcSizePtr >= LZ4_64Klimit))
+ return 0;
+ /* Input too small, no compression (all literals) */
+ if (*srcSizePtr < LZ4_minLength)
+ goto _last_literals;
/* First Byte */
- ip++;
- forwardh = LZ4_HASH64K_VALUE(ip);
+ *srcSizePtr = 0;
+ LZ4_putPosition(ip, ctx->hashTable, tableType, base);
+ ip++; forwardH = LZ4_hashPosition(ip, tableType);
/* Main Loop */
- for (;;) {
- int findmatchattempts = (1U << skipstrength) + 3;
- const u8 *forwardip = ip;
- const u8 *ref;
- u8 *token;
+ for ( ; ; ) {
+ const BYTE *match;
+ BYTE *token;
/* Find a match */
- do {
- u32 h = forwardh;
- int step = findmatchattempts++ >> skipstrength;
- ip = forwardip;
- forwardip = ip + step;
-
- if (forwardip > mflimit)
- goto _last_literals;
-
- forwardh = LZ4_HASH64K_VALUE(forwardip);
- ref = base + hashtable[h];
- hashtable[h] = (u16)(ip - base);
- } while (A32(ref) != A32(ip));
+ {
+ const BYTE *forwardIp = ip;
+ unsigned int step = 1;
+ unsigned int searchMatchNb = 1 << LZ4_SKIPTRIGGER;
+
+ do {
+ U32 h = forwardH;
+
+ ip = forwardIp;
+ forwardIp += step;
+ step = (searchMatchNb++ >> LZ4_SKIPTRIGGER);
+
+ if (unlikely(forwardIp > mflimit))
+ goto _last_literals;
+
+ match = LZ4_getPositionOnHash(h, ctx->hashTable,
+ tableType, base);
+ forwardH = LZ4_hashPosition(forwardIp,
+ tableType);
+ LZ4_putPositionOnHash(ip, h,
+ ctx->hashTable, tableType,
+ base);
+
+ } while (((tableType == byU16)
+ ? 0
+ : (match + MAX_DISTANCE < ip))
+ || (LZ4_read32(match) != LZ4_read32(ip)));
+ }
/* Catch up */
- while ((ip > anchor) && (ref > (u8 *)source)
- && (ip[-1] == ref[-1])) {
+ while ((ip > anchor)
+ && (match > lowLimit)
+ && (unlikely(ip[-1] == match[-1]))) {
ip--;
- ref--;
+ match--;
}
/* Encode Literal length */
- length = (int)(ip - anchor);
- token = op++;
- /* Check output limit */
- if (unlikely(op + length + (2 + 1 + LASTLITERALS)
- + (length >> 8) > oend))
- return 0;
- if (length >= (int)RUN_MASK) {
- *token = (RUN_MASK << ML_BITS);
- len = length - RUN_MASK;
- for (; len > 254 ; len -= 255)
- *op++ = 255;
- *op++ = (u8)len;
- } else
- *token = (length << ML_BITS);
+ {
+ unsigned int litLength = (unsigned int)(ip - anchor);
- /* Copy Literals */
- LZ4_BLINDCOPY(anchor, op, length);
+ token = op++;
+ if (op + ((litLength + 240) / 255)
+ + litLength > oMaxLit) {
+ /* Not enough space for a last match */
+ op--;
+ goto _last_literals;
+ }
+ if (litLength >= RUN_MASK) {
+ unsigned int len = litLength - RUN_MASK;
+ *token = (RUN_MASK<<ML_BITS);
+ for (; len >= 255; len -= 255)
+ *op++ = 255;
+ *op++ = (BYTE)len;
+ } else
+ *token = (BYTE)(litLength << ML_BITS);
+
+ /* Copy Literals */
+ LZ4_wildCopy(op, anchor, op + litLength);
+ op += litLength;
+ }
_next_match:
/* Encode Offset */
- LZ4_WRITE_LITTLEENDIAN_16(op, (u16)(ip - ref));
+ LZ4_writeLE16(op, (U16)(ip - match)); op += 2;
- /* Start Counting */
- ip += MINMATCH;
- /* MinMatch verified */
- ref += MINMATCH;
- anchor = ip;
+ /* Encode MatchLength */
+ {
+ size_t matchLength = LZ4_count(ip + MINMATCH,
+ match + MINMATCH, matchlimit);
- while (ip < MATCHLIMIT - (STEPSIZE - 1)) {
- #if LZ4_ARCH64
- u64 diff = A64(ref) ^ A64(ip);
- #else
- u32 diff = A32(ref) ^ A32(ip);
- #endif
-
- if (!diff) {
- ip += STEPSIZE;
- ref += STEPSIZE;
- continue;
+ if (op + ((matchLength + 240)/255) > oMaxMatch) {
+ /* Match description too long : reduce it */
+ matchLength = (15 - 1) + (oMaxMatch - op) * 255;
}
- ip += LZ4_NBCOMMONBYTES(diff);
- goto _endcount;
- }
- #if LZ4_ARCH64
- if ((ip < (MATCHLIMIT - 3)) && (A32(ref) == A32(ip))) {
- ip += 4;
- ref += 4;
- }
- #endif
- if ((ip < (MATCHLIMIT - 1)) && (A16(ref) == A16(ip))) {
- ip += 2;
- ref += 2;
+ ip += MINMATCH + matchLength;
+
+ if (matchLength >= ML_MASK) {
+ *token += ML_MASK;
+ matchLength -= ML_MASK;
+ while (matchLength >= 255) {
+ matchLength -= 255;
+ *op++ = 255;
+ }
+ *op++ = (BYTE)matchLength;
+ } else
+ *token += (BYTE)(matchLength);
}
- if ((ip < MATCHLIMIT) && (*ref == *ip))
- ip++;
-_endcount:
- /* Encode MatchLength */
- len = (int)(ip - anchor);
- /* Check output limit */
- if (unlikely(op + (1 + LASTLITERALS) + (len >> 8) > oend))
- return 0;
- if (len >= (int)ML_MASK) {
- *token += ML_MASK;
- len -= ML_MASK;
- for (; len > 509 ; len -= 510) {
- *op++ = 255;
- *op++ = 255;
- }
- if (len > 254) {
- len -= 255;
- *op++ = 255;
- }
- *op++ = (u8)len;
- } else
- *token += len;
+ anchor = ip;
- /* Test end of chunk */
- if (ip > mflimit) {
- anchor = ip;
+ /* Test end of block */
+ if (ip > mflimit)
+ break;
+ if (op > oMaxSeq)
break;
- }
/* Fill table */
- hashtable[LZ4_HASH64K_VALUE(ip-2)] = (u16)(ip - 2 - base);
+ LZ4_putPosition(ip - 2, ctx->hashTable, tableType, base);
/* Test next position */
- ref = base + hashtable[LZ4_HASH64K_VALUE(ip)];
- hashtable[LZ4_HASH64K_VALUE(ip)] = (u16)(ip - base);
- if (A32(ref) == A32(ip)) {
- token = op++;
- *token = 0;
+ match = LZ4_getPosition(ip, ctx->hashTable, tableType, base);
+ LZ4_putPosition(ip, ctx->hashTable, tableType, base);
+
+ if ((match + MAX_DISTANCE >= ip)
+ && (LZ4_read32(match) == LZ4_read32(ip))) {
+ token = op++; *token = 0;
goto _next_match;
}
/* Prepare next loop */
- anchor = ip++;
- forwardh = LZ4_HASH64K_VALUE(ip);
+ forwardH = LZ4_hashPosition(++ip, tableType);
}
_last_literals:
/* Encode Last Literals */
- lastrun = (int)(iend - anchor);
- if (op + lastrun + 1 + (lastrun - RUN_MASK + 255) / 255 > oend)
- return 0;
- if (lastrun >= (int)RUN_MASK) {
- *op++ = (RUN_MASK << ML_BITS);
- lastrun -= RUN_MASK;
- for (; lastrun > 254 ; lastrun -= 255)
- *op++ = 255;
- *op++ = (u8)lastrun;
- } else
- *op++ = (lastrun << ML_BITS);
- memcpy(op, anchor, iend - anchor);
- op += iend - anchor;
+ {
+ size_t lastRunSize = (size_t)(iend - anchor);
+
+ if (op + 1 /* token */
+ + ((lastRunSize + 240) / 255) /* litLength */
+ + lastRunSize /* literals */ > oend) {
+ /* adapt lastRunSize to fill 'dst' */
+ lastRunSize = (oend - op) - 1;
+ lastRunSize -= (lastRunSize + 240) / 255;
+ }
+ ip = anchor + lastRunSize;
+
+ if (lastRunSize >= RUN_MASK) {
+ size_t accumulator = lastRunSize - RUN_MASK;
+
+ *op++ = RUN_MASK << ML_BITS;
+ for (; accumulator >= 255; accumulator -= 255)
+ *op++ = 255;
+ *op++ = (BYTE) accumulator;
+ } else {
+ *op++ = (BYTE)(lastRunSize<<ML_BITS);
+ }
+ memcpy(op, anchor, lastRunSize);
+ op += lastRunSize;
+ }
+
/* End */
- return (int)(((char *)op) - dest);
+ *srcSizePtr = (int) (((const char *)ip) - src);
+ return (int) (((char *)op) - dst);
}
-int lz4_compress(const unsigned char *src, size_t src_len,
- unsigned char *dst, size_t *dst_len, void *wrkmem)
+static int LZ4_compress_destSize_extState(
+ LZ4_stream_t *state,
+ const char *src,
+ char *dst,
+ int *srcSizePtr,
+ int targetDstSize)
{
- int ret = -1;
- int out_len = 0;
+#if LZ4_ARCH64
+ const tableType_t tableType = byU32;
+#else
+ const tableType_t tableType = byPtr;
+#endif
- if (src_len < LZ4_64KLIMIT)
- out_len = lz4_compress64kctx(wrkmem, src, dst, src_len,
- lz4_compressbound(src_len));
- else
- out_len = lz4_compressctx(wrkmem, src, dst, src_len,
- lz4_compressbound(src_len));
+ LZ4_resetStream(state);
+
+ if (targetDstSize >= LZ4_COMPRESSBOUND(*srcSizePtr)) {
+ /* compression success is guaranteed */
+ return LZ4_compress_fast_extState(
+ state, src, dst, *srcSizePtr,
+ targetDstSize, 1);
+ } else {
+ if (*srcSizePtr < LZ4_64Klimit)
+ return LZ4_compress_destSize_generic(
+ &state->internal_donotuse,
+ src, dst, srcSizePtr,
+ targetDstSize, byU16);
+ else
+ return LZ4_compress_destSize_generic(
+ &state->internal_donotuse,
+ src, dst, srcSizePtr,
+ targetDstSize, tableType);
+ }
+}
+
+
+int LZ4_compress_destSize(
+ const char *src,
+ char *dst,
+ int *srcSizePtr,
+ int targetDstSize,
+ void *wrkmem)
+{
+ return LZ4_compress_destSize_extState(wrkmem, src, dst, srcSizePtr,
+ targetDstSize);
+}
+EXPORT_SYMBOL(LZ4_compress_destSize);
+
+/*-******************************
+ * Streaming functions
+ ********************************/
+void LZ4_resetStream(LZ4_stream_t *LZ4_stream)
+{
+ memset(LZ4_stream, 0, sizeof(LZ4_stream_t));
+}
+
+int LZ4_loadDict(LZ4_stream_t *LZ4_dict,
+ const char *dictionary, int dictSize)
+{
+ LZ4_stream_t_internal *dict = &LZ4_dict->internal_donotuse;
+ const BYTE *p = (const BYTE *)dictionary;
+ const BYTE * const dictEnd = p + dictSize;
+ const BYTE *base;
+
+ if ((dict->initCheck)
+ || (dict->currentOffset > 1 * GB)) {
+ /* Uninitialized structure, or reuse overflow */
+ LZ4_resetStream(LZ4_dict);
+ }
+
+ if (dictSize < (int)HASH_UNIT) {
+ dict->dictionary = NULL;
+ dict->dictSize = 0;
+ return 0;
+ }
+
+ if ((dictEnd - p) > 64 * KB)
+ p = dictEnd - 64 * KB;
+ dict->currentOffset += 64 * KB;
+ base = p - dict->currentOffset;
+ dict->dictionary = p;
+ dict->dictSize = (U32)(dictEnd - p);
+ dict->currentOffset += dict->dictSize;
+
+ while (p <= dictEnd - HASH_UNIT) {
+ LZ4_putPosition(p, dict->hashTable, byU32, base);
+ p += 3;
+ }
+
+ return dict->dictSize;
+}
+EXPORT_SYMBOL(LZ4_loadDict);
+
+static void LZ4_renormDictT(LZ4_stream_t_internal *LZ4_dict,
+ const BYTE *src)
+{
+ if ((LZ4_dict->currentOffset > 0x80000000) ||
+ ((uptrval)LZ4_dict->currentOffset > (uptrval)src)) {
+ /* address space overflow */
+ /* rescale hash table */
+ U32 const delta = LZ4_dict->currentOffset - 64 * KB;
+ const BYTE *dictEnd = LZ4_dict->dictionary + LZ4_dict->dictSize;
+ int i;
+
+ for (i = 0; i < LZ4_HASH_SIZE_U32; i++) {
+ if (LZ4_dict->hashTable[i] < delta)
+ LZ4_dict->hashTable[i] = 0;
+ else
+ LZ4_dict->hashTable[i] -= delta;
+ }
+ LZ4_dict->currentOffset = 64 * KB;
+ if (LZ4_dict->dictSize > 64 * KB)
+ LZ4_dict->dictSize = 64 * KB;
+ LZ4_dict->dictionary = dictEnd - LZ4_dict->dictSize;
+ }
+}
+
+int LZ4_saveDict(LZ4_stream_t *LZ4_dict, char *safeBuffer, int dictSize)
+{
+ LZ4_stream_t_internal * const dict = &LZ4_dict->internal_donotuse;
+ const BYTE * const previousDictEnd = dict->dictionary + dict->dictSize;
+
+ if ((U32)dictSize > 64 * KB) {
+ /* useless to define a dictionary > 64 * KB */
+ dictSize = 64 * KB;
+ }
+ if ((U32)dictSize > dict->dictSize)
+ dictSize = dict->dictSize;
+
+ memmove(safeBuffer, previousDictEnd - dictSize, dictSize);
+
+ dict->dictionary = (const BYTE *)safeBuffer;
+ dict->dictSize = (U32)dictSize;
+
+ return dictSize;
+}
+EXPORT_SYMBOL(LZ4_saveDict);
+
+int LZ4_compress_fast_continue(LZ4_stream_t *LZ4_stream, const char *source,
+ char *dest, int inputSize, int maxOutputSize, int acceleration)
+{
+ LZ4_stream_t_internal *streamPtr = &LZ4_stream->internal_donotuse;
+ const BYTE * const dictEnd = streamPtr->dictionary
+ + streamPtr->dictSize;
+
+ const BYTE *smallest = (const BYTE *) source;
+
+ if (streamPtr->initCheck) {
+ /* Uninitialized structure detected */
+ return 0;
+ }
+
+ if ((streamPtr->dictSize > 0) && (smallest > dictEnd))
+ smallest = dictEnd;
+
+ LZ4_renormDictT(streamPtr, smallest);
+
+ if (acceleration < 1)
+ acceleration = LZ4_ACCELERATION_DEFAULT;
- if (out_len < 0)
- goto exit;
+ /* Check overlapping input/dictionary space */
+ {
+ const BYTE *sourceEnd = (const BYTE *) source + inputSize;
+
+ if ((sourceEnd > streamPtr->dictionary)
+ && (sourceEnd < dictEnd)) {
+ streamPtr->dictSize = (U32)(dictEnd - sourceEnd);
+ if (streamPtr->dictSize > 64 * KB)
+ streamPtr->dictSize = 64 * KB;
+ if (streamPtr->dictSize < 4)
+ streamPtr->dictSize = 0;
+ streamPtr->dictionary = dictEnd - streamPtr->dictSize;
+ }
+ }
- *dst_len = out_len;
+ /* prefix mode : source data follows dictionary */
+ if (dictEnd == (const BYTE *)source) {
+ int result;
+
+ if ((streamPtr->dictSize < 64 * KB) &&
+ (streamPtr->dictSize < streamPtr->currentOffset)) {
+ result = LZ4_compress_generic(
+ streamPtr, source, dest, inputSize,
+ maxOutputSize, limitedOutput, byU32,
+ withPrefix64k, dictSmall, acceleration);
+ } else {
+ result = LZ4_compress_generic(
+ streamPtr, source, dest, inputSize,
+ maxOutputSize, limitedOutput, byU32,
+ withPrefix64k, noDictIssue, acceleration);
+ }
+ streamPtr->dictSize += (U32)inputSize;
+ streamPtr->currentOffset += (U32)inputSize;
+ return result;
+ }
- return 0;
-exit:
- return ret;
+ /* external dictionary mode */
+ {
+ int result;
+
+ if ((streamPtr->dictSize < 64 * KB) &&
+ (streamPtr->dictSize < streamPtr->currentOffset)) {
+ result = LZ4_compress_generic(
+ streamPtr, source, dest, inputSize,
+ maxOutputSize, limitedOutput, byU32,
+ usingExtDict, dictSmall, acceleration);
+ } else {
+ result = LZ4_compress_generic(
+ streamPtr, source, dest, inputSize,
+ maxOutputSize, limitedOutput, byU32,
+ usingExtDict, noDictIssue, acceleration);
+ }
+ streamPtr->dictionary = (const BYTE *)source;
+ streamPtr->dictSize = (U32)inputSize;
+ streamPtr->currentOffset += (U32)inputSize;
+ return result;
+ }
+}
+EXPORT_SYMBOL(LZ4_compress_fast_continue);
+
+/*-******************************
+ * For backwards compatibility
+ ********************************/
+int lz4_compress(const unsigned char *src, size_t src_len, unsigned char *dst,
+ size_t *dst_len, void *wrkmem) {
+ *dst_len = LZ4_compress_default(src, dst, src_len,
+ *dst_len, wrkmem);
+
+ /*
+ * Prior lz4_compress will return -1 in case of error
+ * and 0 on success
+ * while new LZ4_compress_fast/default
+ * returns 0 in case of error
+ * and the output length on success
+ */
+ if (!*dst_len)
+ return -1;
+ else
+ return 0;
}
EXPORT_SYMBOL(lz4_compress);
diff --git a/lib/lz4/lz4_decompress.c b/lib/lz4/lz4_decompress.c
index 6d940c72b5fc..b5e00a19a7b4 100644
--- a/lib/lz4/lz4_decompress.c
+++ b/lib/lz4/lz4_decompress.c
@@ -1,25 +1,16 @@
/*
- * LZ4 Decompressor for Linux kernel
- *
- * Copyright (C) 2013, LG Electronics, Kyungsik Lee <kyungsik.lee@lge.com>
- *
- * Based on LZ4 implementation by Yann Collet.
- *
* LZ4 - Fast LZ compression algorithm
- * Copyright (C) 2011-2012, Yann Collet.
- * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
- *
+ * Copyright (C) 2011 - 2016, Yann Collet.
+ * BSD 2 - Clause License (http://www.opensource.org/licenses/bsd - license.php)
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
- *
- * * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * * Redistributions in binary form must reproduce the above
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
- *
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
@@ -31,313 +22,529 @@
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * You can contact the author at :
+ * - LZ4 homepage : http://www.lz4.org
+ * - LZ4 source repository : https://github.com/lz4/lz4
*
- * You can contact the author at :
- * - LZ4 homepage : http://fastcompression.blogspot.com/p/lz4.html
- * - LZ4 source repository : http://code.google.com/p/lz4/
+ * Changed for kernel usage by:
+ * Sven Schmidt <4sschmid@informatik.uni-hamburg.de>
*/
-#ifndef STATIC
+/*-************************************
+ * Dependencies
+ **************************************/
+#include <linux/lz4.h>
+#include "lz4defs.h"
+#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h>
-#endif
-#include <linux/lz4.h>
-
#include <asm/unaligned.h>
-#include "lz4defs.h"
-
-static const int dec32table[] = {0, 3, 2, 3, 0, 0, 0, 0};
-#if LZ4_ARCH64
-static const int dec64table[] = {0, 0, 0, -1, 0, 1, 2, 3};
-#endif
-
-static int lz4_uncompress(const char *source, char *dest, int osize)
+/*-*****************************
+ * Decompression functions
+ *******************************/
+/* LZ4_decompress_generic() :
+ * This generic decompression function cover all use cases.
+ * It shall be instantiated several times, using different sets of directives
+ * Note that it is important this generic function is really inlined,
+ * in order to remove useless branches during compilation optimization.
+ */
+static FORCE_INLINE int LZ4_decompress_generic(
+ const char * const source,
+ char * const dest,
+ int inputSize,
+ /*
+ * If endOnInput == endOnInputSize,
+ * this value is the max size of Output Buffer.
+ */
+ int outputSize,
+ /* endOnOutputSize, endOnInputSize */
+ int endOnInput,
+ /* full, partial */
+ int partialDecoding,
+ /* only used if partialDecoding == partial */
+ int targetOutputSize,
+ /* noDict, withPrefix64k, usingExtDict */
+ int dict,
+ /* == dest when no prefix */
+ const BYTE * const lowPrefix,
+ /* only if dict == usingExtDict */
+ const BYTE * const dictStart,
+ /* note : = 0 if noDict */
+ const size_t dictSize
+ )
{
+ /* Local Variables */
const BYTE *ip = (const BYTE *) source;
- const BYTE *ref;
+ const BYTE * const iend = ip + inputSize;
+
BYTE *op = (BYTE *) dest;
- BYTE * const oend = op + osize;
+ BYTE * const oend = op + outputSize;
BYTE *cpy;
- unsigned token;
- size_t length;
+ BYTE *oexit = op + targetOutputSize;
+ const BYTE * const lowLimit = lowPrefix - dictSize;
+
+ const BYTE * const dictEnd = (const BYTE *)dictStart + dictSize;
+ const unsigned int dec32table[] = { 0, 1, 2, 1, 4, 4, 4, 4 };
+ const int dec64table[] = { 0, 0, 0, -1, 0, 1, 2, 3 };
+ const int safeDecode = (endOnInput == endOnInputSize);
+ const int checkOffset = ((safeDecode) && (dictSize < (int)(64 * KB)));
+
+ /* Special cases */
+ /* targetOutputSize too high => decode everything */
+ if ((partialDecoding) && (oexit > oend - MFLIMIT))
+ oexit = oend - MFLIMIT;
+
+ /* Empty output buffer */
+ if ((endOnInput) && (unlikely(outputSize == 0)))
+ return ((inputSize == 1) && (*ip == 0)) ? 0 : -1;
+
+ if ((!endOnInput) && (unlikely(outputSize == 0)))
+ return (*ip == 0 ? 1 : -1);
+
+ /* Main Loop : decode sequences */
while (1) {
+ size_t length;
+ const BYTE *match;
+ size_t offset;
+
+ /* get literal length */
+ unsigned int const token = *ip++;
+
+ length = token>>ML_BITS;
- /* get runlength */
- token = *ip++;
- length = (token >> ML_BITS);
if (length == RUN_MASK) {
- size_t len;
+ unsigned int s;
- len = *ip++;
- for (; len == 255; length += 255)
- len = *ip++;
- if (unlikely(length > (size_t)(length + len)))
+ do {
+ s = *ip++;
+ length += s;
+ } while (likely(endOnInput
+ ? ip < iend - RUN_MASK
+ : 1) & (s == 255));
+
+ if ((safeDecode)
+ && unlikely(
+ (size_t)(op + length) < (size_t)(op))) {
+ /* overflow detection */
goto _output_error;
- length += len;
+ }
+ if ((safeDecode)
+ && unlikely(
+ (size_t)(ip + length) < (size_t)(ip))) {
+ /* overflow detection */
+ goto _output_error;
+ }
}
/* copy literals */
cpy = op + length;
- if (unlikely(cpy > oend - COPYLENGTH)) {
- /*
- * Error: not enough place for another match
- * (min 4) + 5 literals
- */
- if (cpy != oend)
- goto _output_error;
+ if (((endOnInput) && ((cpy > (partialDecoding ? oexit : oend - MFLIMIT))
+ || (ip + length > iend - (2 + 1 + LASTLITERALS))))
+ || ((!endOnInput) && (cpy > oend - WILDCOPYLENGTH))) {
+ if (partialDecoding) {
+ if (cpy > oend) {
+ /*
+ * Error :
+ * write attempt beyond end of output buffer
+ */
+ goto _output_error;
+ }
+ if ((endOnInput)
+ && (ip + length > iend)) {
+ /*
+ * Error :
+ * read attempt beyond
+ * end of input buffer
+ */
+ goto _output_error;
+ }
+ } else {
+ if ((!endOnInput)
+ && (cpy != oend)) {
+ /*
+ * Error :
+ * block decoding must
+ * stop exactly there
+ */
+ goto _output_error;
+ }
+ if ((endOnInput)
+ && ((ip + length != iend)
+ || (cpy > oend))) {
+ /*
+ * Error :
+ * input must be consumed
+ */
+ goto _output_error;
+ }
+ }
memcpy(op, ip, length);
ip += length;
- break; /* EOF */
+ op += length;
+ /* Necessarily EOF, due to parsing restrictions */
+ break;
}
- LZ4_WILDCOPY(ip, op, cpy);
- ip -= (op - cpy);
+
+ LZ4_wildCopy(op, ip, cpy);
+ ip += length;
op = cpy;
/* get offset */
- LZ4_READ_LITTLEENDIAN_16(ref, cpy, ip);
+ offset = LZ4_readLE16(ip);
ip += 2;
+ match = op - offset;
- /* Error: offset create reference outside destination buffer */
- if (unlikely(ref < (BYTE *const) dest))
+ if ((checkOffset) && (unlikely(match < lowLimit))) {
+ /* Error : offset outside buffers */
goto _output_error;
+ }
+
+ /* costs ~1%; silence an msan warning when offset == 0 */
+ LZ4_write32(op, (U32)offset);
/* get matchlength */
length = token & ML_MASK;
if (length == ML_MASK) {
- for (; *ip == 255; length += 255)
- ip++;
- if (unlikely(length > (size_t)(length + *ip)))
+ unsigned int s;
+
+ do {
+ s = *ip++;
+
+ if ((endOnInput) && (ip > iend - LASTLITERALS))
+ goto _output_error;
+
+ length += s;
+ } while (s == 255);
+
+ if ((safeDecode)
+ && unlikely(
+ (size_t)(op + length) < (size_t)op)) {
+ /* overflow detection */
goto _output_error;
- length += *ip++;
+ }
}
- /* copy repeated sequence */
- if (unlikely((op - ref) < STEPSIZE)) {
-#if LZ4_ARCH64
- int dec64 = dec64table[op - ref];
-#else
- const int dec64 = 0;
-#endif
- op[0] = ref[0];
- op[1] = ref[1];
- op[2] = ref[2];
- op[3] = ref[3];
- op += 4;
- ref += 4;
- ref -= dec32table[op-ref];
- PUT4(ref, op);
- op += STEPSIZE - 4;
- ref -= dec64;
+ length += MINMATCH;
+
+ /* check external dictionary */
+ if ((dict == usingExtDict) && (match < lowPrefix)) {
+ if (unlikely(op + length > oend - LASTLITERALS)) {
+ /* doesn't respect parsing restriction */
+ goto _output_error;
+ }
+
+ if (length <= (size_t)(lowPrefix - match)) {
+ /*
+ * match can be copied as a single segment
+ * from external dictionary
+ */
+ memmove(op, dictEnd - (lowPrefix - match),
+ length);
+ op += length;
+ } else {
+ /*
+ * match encompass external
+ * dictionary and current block
+ */
+ size_t const copySize = (size_t)(lowPrefix - match);
+ size_t const restSize = length - copySize;
+
+ memcpy(op, dictEnd - copySize, copySize);
+ op += copySize;
+
+ if (restSize > (size_t)(op - lowPrefix)) {
+ /* overlap copy */
+ BYTE * const endOfMatch = op + restSize;
+ const BYTE *copyFrom = lowPrefix;
+
+ while (op < endOfMatch)
+ *op++ = *copyFrom++;
+ } else {
+ memcpy(op, lowPrefix, restSize);
+ op += restSize;
+ }
+ }
+
+ continue;
+ }
+
+ /* copy match within block */
+ cpy = op + length;
+
+ if (unlikely(offset < 8)) {
+ const int dec64 = dec64table[offset];
+
+ op[0] = match[0];
+ op[1] = match[1];
+ op[2] = match[2];
+ op[3] = match[3];
+ match += dec32table[offset];
+ memcpy(op + 4, match, 4);
+ match -= dec64;
} else {
- LZ4_COPYSTEP(ref, op);
+ LZ4_copy8(op, match);
+ match += 8;
}
- cpy = op + length - (STEPSIZE - 4);
- if (cpy > (oend - COPYLENGTH)) {
- /* Error: request to write beyond destination buffer */
- if (cpy > oend)
- goto _output_error;
-#if LZ4_ARCH64
- if ((ref + COPYLENGTH) > oend)
-#else
- if ((ref + COPYLENGTH) > oend ||
- (op + COPYLENGTH) > oend)
-#endif
+ op += 8;
+
+ if (unlikely(cpy > oend - 12)) {
+ BYTE * const oCopyLimit = oend - (WILDCOPYLENGTH - 1);
+
+ if (cpy > oend - LASTLITERALS) {
+ /*
+ * Error : last LASTLITERALS bytes
+ * must be literals (uncompressed)
+ */
goto _output_error;
- LZ4_SECURECOPY(ref, op, (oend - COPYLENGTH));
+ }
+
+ if (op < oCopyLimit) {
+ LZ4_wildCopy(op, match, oCopyLimit);
+ match += oCopyLimit - op;
+ op = oCopyLimit;
+ }
+
while (op < cpy)
- *op++ = *ref++;
- op = cpy;
- /*
- * Check EOF (should never happen, since last 5 bytes
- * are supposed to be literals)
- */
- if (op == oend)
- goto _output_error;
- continue;
+ *op++ = *match++;
+ } else {
+ LZ4_copy8(op, match);
+
+ if (length > 16)
+ LZ4_wildCopy(op + 8, match + 8, cpy);
}
- LZ4_SECURECOPY(ref, op, cpy);
+
op = cpy; /* correction */
}
+
/* end of decoding */
- return (int) (((char *)ip) - source);
+ if (endOnInput) {
+ /* Nb of output bytes decoded */
+ return (int) (((char *)op) - dest);
+ } else {
+ /* Nb of input bytes read */
+ return (int) (((const char *)ip) - source);
+ }
- /* write overflow error detected */
+ /* Overflow error detected */
_output_error:
return -1;
}
-static int lz4_uncompress_unknownoutputsize(const char *source, char *dest,
- int isize, size_t maxoutputsize)
+int LZ4_decompress_safe(const char *source, char *dest,
+ int compressedSize, int maxDecompressedSize)
{
- const BYTE *ip = (const BYTE *) source;
- const BYTE *const iend = ip + isize;
- const BYTE *ref;
-
+ return LZ4_decompress_generic(source, dest, compressedSize,
+ maxDecompressedSize, endOnInputSize, full, 0,
+ noDict, (BYTE *)dest, NULL, 0);
+}
- BYTE *op = (BYTE *) dest;
- BYTE * const oend = op + maxoutputsize;
- BYTE *cpy;
+int LZ4_decompress_safe_partial(const char *source, char *dest,
+ int compressedSize, int targetOutputSize, int maxDecompressedSize)
+{
+ return LZ4_decompress_generic(source, dest, compressedSize,
+ maxDecompressedSize, endOnInputSize, partial,
+ targetOutputSize, noDict, (BYTE *)dest, NULL, 0);
+}
- /* Main Loop */
- while (ip < iend) {
+int LZ4_decompress_fast(const char *source, char *dest, int originalSize)
+{
+ return LZ4_decompress_generic(source, dest, 0, originalSize,
+ endOnOutputSize, full, 0, withPrefix64k,
+ (BYTE *)(dest - 64 * KB), NULL, 64 * KB);
+}
- unsigned token;
- size_t length;
+int LZ4_setStreamDecode(LZ4_streamDecode_t *LZ4_streamDecode,
+ const char *dictionary, int dictSize)
+{
+ LZ4_streamDecode_t_internal *lz4sd = (LZ4_streamDecode_t_internal *) LZ4_streamDecode;
- /* get runlength */
- token = *ip++;
- length = (token >> ML_BITS);
- if (length == RUN_MASK) {
- int s = 255;
- while ((ip < iend) && (s == 255)) {
- s = *ip++;
- if (unlikely(length > (size_t)(length + s)))
- goto _output_error;
- length += s;
- }
- }
- /* copy literals */
- cpy = op + length;
- if ((cpy > oend - COPYLENGTH) ||
- (ip + length > iend - COPYLENGTH)) {
-
- if (cpy > oend)
- goto _output_error;/* writes beyond buffer */
-
- if (ip + length != iend)
- goto _output_error;/*
- * Error: LZ4 format requires
- * to consume all input
- * at this stage
- */
- memcpy(op, ip, length);
- op += length;
- break;/* Necessarily EOF, due to parsing restrictions */
- }
- LZ4_WILDCOPY(ip, op, cpy);
- ip -= (op - cpy);
- op = cpy;
+ lz4sd->prefixSize = (size_t) dictSize;
+ lz4sd->prefixEnd = (const BYTE *) dictionary + dictSize;
+ lz4sd->externalDict = NULL;
+ lz4sd->extDictSize = 0;
+ return 1;
+}
- /* get offset */
- LZ4_READ_LITTLEENDIAN_16(ref, cpy, ip);
- ip += 2;
- if (ref < (BYTE * const) dest)
- goto _output_error;
- /*
- * Error : offset creates reference
- * outside of destination buffer
- */
+/*
+ * *_continue() :
+ * These decoding functions allow decompression of multiple blocks
+ * in "streaming" mode.
+ * Previously decoded blocks must still be available at the memory
+ * position where they were decoded.
+ * If it's not possible, save the relevant part of
+ * decoded data into a safe buffer,
+ * and indicate where it stands using LZ4_setStreamDecode()
+ */
+int LZ4_decompress_safe_continue(LZ4_streamDecode_t *LZ4_streamDecode,
+ const char *source, char *dest, int compressedSize, int maxOutputSize)
+{
+ LZ4_streamDecode_t_internal *lz4sd = &LZ4_streamDecode->internal_donotuse;
+ int result;
+
+ if (lz4sd->prefixEnd == (BYTE *)dest) {
+ result = LZ4_decompress_generic(source, dest,
+ compressedSize,
+ maxOutputSize,
+ endOnInputSize, full, 0,
+ usingExtDict, lz4sd->prefixEnd - lz4sd->prefixSize,
+ lz4sd->externalDict,
+ lz4sd->extDictSize);
+
+ if (result <= 0)
+ return result;
+
+ lz4sd->prefixSize += result;
+ lz4sd->prefixEnd += result;
+ } else {
+ lz4sd->extDictSize = lz4sd->prefixSize;
+ lz4sd->externalDict = lz4sd->prefixEnd - lz4sd->extDictSize;
+ result = LZ4_decompress_generic(source, dest,
+ compressedSize, maxOutputSize,
+ endOnInputSize, full, 0,
+ usingExtDict, (BYTE *)dest,
+ lz4sd->externalDict, lz4sd->extDictSize);
+ if (result <= 0)
+ return result;
+ lz4sd->prefixSize = result;
+ lz4sd->prefixEnd = (BYTE *)dest + result;
+ }
- /* get matchlength */
- length = (token & ML_MASK);
- if (length == ML_MASK) {
- while (ip < iend) {
- int s = *ip++;
- if (unlikely(length > (size_t)(length + s)))
- goto _output_error;
- length += s;
- if (s == 255)
- continue;
- break;
- }
- }
+ return result;
+}
- /* copy repeated sequence */
- if (unlikely((op - ref) < STEPSIZE)) {
-#if LZ4_ARCH64
- int dec64 = dec64table[op - ref];
-#else
- const int dec64 = 0;
-#endif
- op[0] = ref[0];
- op[1] = ref[1];
- op[2] = ref[2];
- op[3] = ref[3];
- op += 4;
- ref += 4;
- ref -= dec32table[op - ref];
- PUT4(ref, op);
- op += STEPSIZE - 4;
- ref -= dec64;
- } else {
- LZ4_COPYSTEP(ref, op);
- }
- cpy = op + length - (STEPSIZE-4);
- if (cpy > oend - COPYLENGTH) {
- if (cpy > oend)
- goto _output_error; /* write outside of buf */
-#if LZ4_ARCH64
- if ((ref + COPYLENGTH) > oend)
-#else
- if ((ref + COPYLENGTH) > oend ||
- (op + COPYLENGTH) > oend)
-#endif
- goto _output_error;
- LZ4_SECURECOPY(ref, op, (oend - COPYLENGTH));
- while (op < cpy)
- *op++ = *ref++;
- op = cpy;
- /*
- * Check EOF (should never happen, since last 5 bytes
- * are supposed to be literals)
- */
- if (op == oend)
- goto _output_error;
- continue;
- }
- LZ4_SECURECOPY(ref, op, cpy);
- op = cpy; /* correction */
+int LZ4_decompress_fast_continue(LZ4_streamDecode_t *LZ4_streamDecode,
+ const char *source, char *dest, int originalSize)
+{
+ LZ4_streamDecode_t_internal *lz4sd = &LZ4_streamDecode->internal_donotuse;
+ int result;
+
+ if (lz4sd->prefixEnd == (BYTE *)dest) {
+ result = LZ4_decompress_generic(source, dest, 0, originalSize,
+ endOnOutputSize, full, 0,
+ usingExtDict,
+ lz4sd->prefixEnd - lz4sd->prefixSize,
+ lz4sd->externalDict, lz4sd->extDictSize);
+
+ if (result <= 0)
+ return result;
+
+ lz4sd->prefixSize += originalSize;
+ lz4sd->prefixEnd += originalSize;
+ } else {
+ lz4sd->extDictSize = lz4sd->prefixSize;
+ lz4sd->externalDict = lz4sd->prefixEnd - lz4sd->extDictSize;
+ result = LZ4_decompress_generic(source, dest, 0, originalSize,
+ endOnOutputSize, full, 0,
+ usingExtDict, (BYTE *)dest,
+ lz4sd->externalDict, lz4sd->extDictSize);
+ if (result <= 0)
+ return result;
+ lz4sd->prefixSize = originalSize;
+ lz4sd->prefixEnd = (BYTE *)dest + originalSize;
}
- /* end of decoding */
- return (int) (((char *) op) - dest);
- /* write overflow error detected */
-_output_error:
- return -1;
+ return result;
}
-int lz4_decompress(const unsigned char *src, size_t *src_len,
- unsigned char *dest, size_t actual_dest_len)
+/*
+ * Advanced decoding functions :
+ * *_usingDict() :
+ * These decoding functions work the same as "_continue" ones,
+ * the dictionary must be explicitly provided within parameters
+ */
+static FORCE_INLINE int LZ4_decompress_usingDict_generic(const char *source,
+ char *dest, int compressedSize, int maxOutputSize, int safe,
+ const char *dictStart, int dictSize)
{
- int ret = -1;
- int input_len = 0;
-
- input_len = lz4_uncompress(src, dest, actual_dest_len);
- if (input_len < 0)
- goto exit_0;
- *src_len = input_len;
+ if (dictSize == 0)
+ return LZ4_decompress_generic(source, dest,
+ compressedSize, maxOutputSize, safe, full, 0,
+ noDict, (BYTE *)dest, NULL, 0);
+ if (dictStart + dictSize == dest) {
+ if (dictSize >= (int)(64 * KB - 1))
+ return LZ4_decompress_generic(source, dest,
+ compressedSize, maxOutputSize, safe, full, 0,
+ withPrefix64k, (BYTE *)dest - 64 * KB, NULL, 0);
+ return LZ4_decompress_generic(source, dest, compressedSize,
+ maxOutputSize, safe, full, 0, noDict,
+ (BYTE *)dest - dictSize, NULL, 0);
+ }
+ return LZ4_decompress_generic(source, dest, compressedSize,
+ maxOutputSize, safe, full, 0, usingExtDict,
+ (BYTE *)dest, (const BYTE *)dictStart, dictSize);
+}
- return 0;
-exit_0:
- return ret;
+int LZ4_decompress_safe_usingDict(const char *source, char *dest,
+ int compressedSize, int maxOutputSize,
+ const char *dictStart, int dictSize)
+{
+ return LZ4_decompress_usingDict_generic(source, dest,
+ compressedSize, maxOutputSize, 1, dictStart, dictSize);
}
-#ifndef STATIC
-EXPORT_SYMBOL(lz4_decompress);
-#endif
-int lz4_decompress_unknownoutputsize(const unsigned char *src, size_t src_len,
- unsigned char *dest, size_t *dest_len)
+int LZ4_decompress_fast_usingDict(const char *source, char *dest,
+ int originalSize, const char *dictStart, int dictSize)
{
- int ret = -1;
- int out_len = 0;
-
- out_len = lz4_uncompress_unknownoutputsize(src, dest, src_len,
- *dest_len);
- if (out_len < 0)
- goto exit_0;
- *dest_len = out_len;
-
- return 0;
-exit_0:
- return ret;
+ return LZ4_decompress_usingDict_generic(source, dest, 0,
+ originalSize, 0, dictStart, dictSize);
}
+
+/*-******************************
+ * For backwards compatibility
+ ********************************/
+int lz4_decompress_unknownoutputsize(const unsigned char *src,
+ size_t src_len, unsigned char *dest, size_t *dest_len) {
+ *dest_len = LZ4_decompress_safe(src, dest,
+ src_len, *dest_len);
+
+ /*
+ * Prior lz4_decompress_unknownoutputsize will return
+ * 0 for success and a negative result for error
+ * new LZ4_decompress_safe returns
+ * - the length of data read on success
+ * - and also a negative result on error
+ * meaning when result > 0, we just return 0 here
+ */
+ if (src_len > 0)
+ return 0;
+ else
+ return -1;
+}
+
+int lz4_decompress(const unsigned char *src, size_t *src_len,
+ unsigned char *dest, size_t actual_dest_len) {
+ *src_len = LZ4_decompress_fast(src, dest, actual_dest_len);
+
+ /*
+ * Prior lz4_decompress will return
+ * 0 for success and a negative result for error
+ * new LZ4_decompress_fast returns
+ * - the length of data read on success
+ * - and also a negative result on error
+ * meaning when result > 0, we just return 0 here
+ */
+ if (*src_len > 0)
+ return 0;
+ else
+ return -1;
+}
+
#ifndef STATIC
+EXPORT_SYMBOL(LZ4_decompress_safe);
+EXPORT_SYMBOL(LZ4_decompress_safe_partial);
+EXPORT_SYMBOL(LZ4_decompress_fast);
+EXPORT_SYMBOL(LZ4_setStreamDecode);
+EXPORT_SYMBOL(LZ4_decompress_safe_continue);
+EXPORT_SYMBOL(LZ4_decompress_fast_continue);
+EXPORT_SYMBOL(LZ4_decompress_safe_usingDict);
+EXPORT_SYMBOL(LZ4_decompress_fast_usingDict);
EXPORT_SYMBOL(lz4_decompress_unknownoutputsize);
+EXPORT_SYMBOL(lz4_decompress);
MODULE_LICENSE("Dual BSD/GPL");
-MODULE_DESCRIPTION("LZ4 Decompressor");
+MODULE_DESCRIPTION("LZ4 decompressor");
#endif
diff --git a/lib/lz4/lz4defs.h b/lib/lz4/lz4defs.h
index c79d7ea8a38e..00a0b58a0871 100644
--- a/lib/lz4/lz4defs.h
+++ b/lib/lz4/lz4defs.h
@@ -1,157 +1,227 @@
+#ifndef __LZ4DEFS_H__
+#define __LZ4DEFS_H__
+
/*
- * lz4defs.h -- architecture specific defines
- *
- * Copyright (C) 2013, LG Electronics, Kyungsik Lee <kyungsik.lee@lge.com>
+ * lz4defs.h -- common and architecture specific defines for the kernel usage
+
+ * LZ4 - Fast LZ compression algorithm
+ * Copyright (C) 2011-2016, Yann Collet.
+ * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * You can contact the author at :
+ * - LZ4 homepage : http://www.lz4.org
+ * - LZ4 source repository : https://github.com/lz4/lz4
*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
+ * Changed for kernel usage by:
+ * Sven Schmidt <4sschmid@informatik.uni-hamburg.de>
*/
-/*
- * Detects 64 bits mode
- */
+#include <asm/unaligned.h>
+#include <linux/string.h> /* memset, memcpy */
+
+#define FORCE_INLINE __always_inline
+
+/*-************************************
+ * Basic Types
+ **************************************/
+#include <linux/types.h>
+
+typedef uint8_t BYTE;
+typedef uint16_t U16;
+typedef uint32_t U32;
+typedef int32_t S32;
+typedef uint64_t U64;
+typedef uintptr_t uptrval;
+
+/*-************************************
+ * Architecture specifics
+ **************************************/
#if defined(CONFIG_64BIT)
#define LZ4_ARCH64 1
#else
#define LZ4_ARCH64 0
#endif
-/*
- * Architecture-specific macros
- */
-#define BYTE u8
-typedef struct _U16_S { u16 v; } U16_S;
-typedef struct _U32_S { u32 v; } U32_S;
-typedef struct _U64_S { u64 v; } U64_S;
-#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
-
-#define A16(x) (((U16_S *)(x))->v)
-#define A32(x) (((U32_S *)(x))->v)
-#define A64(x) (((U64_S *)(x))->v)
-
-#define PUT4(s, d) (A32(d) = A32(s))
-#define PUT8(s, d) (A64(d) = A64(s))
-
-#define LZ4_READ_LITTLEENDIAN_16(d, s, p) \
- (d = s - A16(p))
-
-#define LZ4_WRITE_LITTLEENDIAN_16(p, v) \
- do { \
- A16(p) = v; \
- p += 2; \
- } while (0)
-#else /* CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS */
-
-#define A64(x) get_unaligned((u64 *)&(((U16_S *)(x))->v))
-#define A32(x) get_unaligned((u32 *)&(((U16_S *)(x))->v))
-#define A16(x) get_unaligned((u16 *)&(((U16_S *)(x))->v))
-
-#define PUT4(s, d) \
- put_unaligned(get_unaligned((const u32 *) s), (u32 *) d)
-#define PUT8(s, d) \
- put_unaligned(get_unaligned((const u64 *) s), (u64 *) d)
-
-#define LZ4_READ_LITTLEENDIAN_16(d, s, p) \
- (d = s - get_unaligned_le16(p))
-
-#define LZ4_WRITE_LITTLEENDIAN_16(p, v) \
- do { \
- put_unaligned_le16(v, (u16 *)(p)); \
- p += 2; \
- } while (0)
+#if defined(__LITTLE_ENDIAN)
+#define LZ4_LITTLE_ENDIAN 1
+#else
+#define LZ4_LITTLE_ENDIAN 0
#endif
-#define COPYLENGTH 8
-#define ML_BITS 4
-#define ML_MASK ((1U << ML_BITS) - 1)
+/*-************************************
+ * Constants
+ **************************************/
+#define MINMATCH 4
+
+#define WILDCOPYLENGTH 8
+#define LASTLITERALS 5
+#define MFLIMIT (WILDCOPYLENGTH + MINMATCH)
+
+/* Increase this value ==> compression run slower on incompressible data */
+#define LZ4_SKIPTRIGGER 6
+
+#define HASH_UNIT sizeof(size_t)
+
+#define KB (1 << 10)
+#define MB (1 << 20)
+#define GB (1U << 30)
+
+#define MAXD_LOG 16
+#define MAX_DISTANCE ((1 << MAXD_LOG) - 1)
+#define STEPSIZE sizeof(size_t)
+
+#define ML_BITS 4
+#define ML_MASK ((1U << ML_BITS) - 1)
#define RUN_BITS (8 - ML_BITS)
#define RUN_MASK ((1U << RUN_BITS) - 1)
-#define MEMORY_USAGE 14
-#define MINMATCH 4
-#define SKIPSTRENGTH 6
-#define LASTLITERALS 5
-#define MFLIMIT (COPYLENGTH + MINMATCH)
-#define MINLENGTH (MFLIMIT + 1)
-#define MAXD_LOG 16
-#define MAXD (1 << MAXD_LOG)
-#define MAXD_MASK (u32)(MAXD - 1)
-#define MAX_DISTANCE (MAXD - 1)
-#define HASH_LOG (MAXD_LOG - 1)
-#define HASHTABLESIZE (1 << HASH_LOG)
-#define MAX_NB_ATTEMPTS 256
-#define OPTIMAL_ML (int)((ML_MASK-1)+MINMATCH)
-#define LZ4_64KLIMIT ((1<<16) + (MFLIMIT - 1))
-#define HASHLOG64K ((MEMORY_USAGE - 2) + 1)
-#define HASH64KTABLESIZE (1U << HASHLOG64K)
-#define LZ4_HASH_VALUE(p) (((A32(p)) * 2654435761U) >> \
- ((MINMATCH * 8) - (MEMORY_USAGE-2)))
-#define LZ4_HASH64K_VALUE(p) (((A32(p)) * 2654435761U) >> \
- ((MINMATCH * 8) - HASHLOG64K))
-#define HASH_VALUE(p) (((A32(p)) * 2654435761U) >> \
- ((MINMATCH * 8) - HASH_LOG))
-
-#if LZ4_ARCH64/* 64-bit */
-#define STEPSIZE 8
-
-#define LZ4_COPYSTEP(s, d) \
- do { \
- PUT8(s, d); \
- d += 8; \
- s += 8; \
- } while (0)
-
-#define LZ4_COPYPACKET(s, d) LZ4_COPYSTEP(s, d)
-
-#define LZ4_SECURECOPY(s, d, e) \
- do { \
- if (d < e) { \
- LZ4_WILDCOPY(s, d, e); \
- } \
- } while (0)
-#define HTYPE u32
-
-#ifdef __BIG_ENDIAN
-#define LZ4_NBCOMMONBYTES(val) (__builtin_clzll(val) >> 3)
+
+/*-************************************
+ * Reading and writing into memory
+ **************************************/
+static FORCE_INLINE U16 LZ4_read16(const void *ptr)
+{
+ return get_unaligned((const U16 *)ptr);
+}
+
+static FORCE_INLINE U32 LZ4_read32(const void *ptr)
+{
+ return get_unaligned((const U32 *)ptr);
+}
+
+static FORCE_INLINE size_t LZ4_read_ARCH(const void *ptr)
+{
+ return get_unaligned((const size_t *)ptr);
+}
+
+static FORCE_INLINE void LZ4_write16(void *memPtr, U16 value)
+{
+ put_unaligned(value, (U16 *)memPtr);
+}
+
+static FORCE_INLINE void LZ4_write32(void *memPtr, U32 value)
+{
+ put_unaligned(value, (U32 *)memPtr);
+}
+
+static FORCE_INLINE U16 LZ4_readLE16(const void *memPtr)
+{
+ return get_unaligned_le16(memPtr);
+}
+
+static FORCE_INLINE void LZ4_writeLE16(void *memPtr, U16 value)
+{
+ return put_unaligned_le16(value, memPtr);
+}
+
+static FORCE_INLINE void LZ4_copy8(void *dst, const void *src)
+{
+#if LZ4_ARCH64
+ U64 a = get_unaligned((const U64 *)src);
+
+ put_unaligned(a, (U64 *)dst);
+#else
+ U32 a = get_unaligned((const U32 *)src);
+ U32 b = get_unaligned((const U32 *)src + 1);
+
+ put_unaligned(a, (U32 *)dst);
+ put_unaligned(b, (U32 *)dst + 1);
+#endif
+}
+
+/*
+ * customized variant of memcpy,
+ * which can overwrite up to 7 bytes beyond dstEnd
+ */
+static FORCE_INLINE void LZ4_wildCopy(void *dstPtr,
+ const void *srcPtr, void *dstEnd)
+{
+ BYTE *d = (BYTE *)dstPtr;
+ const BYTE *s = (const BYTE *)srcPtr;
+ BYTE *const e = (BYTE *)dstEnd;
+
+ do {
+ LZ4_copy8(d, s);
+ d += 8;
+ s += 8;
+ } while (d < e);
+}
+
+static FORCE_INLINE unsigned int LZ4_NbCommonBytes(register size_t val)
+{
+#if LZ4_LITTLE_ENDIAN
+ return __ffs(val) >> 3;
#else
-#define LZ4_NBCOMMONBYTES(val) (__builtin_ctzll(val) >> 3)
+ return (BITS_PER_LONG - 1 - __fls(val)) >> 3;
+#endif
+}
+
+static FORCE_INLINE unsigned int LZ4_count(
+ const BYTE *pIn,
+ const BYTE *pMatch,
+ const BYTE *pInLimit)
+{
+ const BYTE *const pStart = pIn;
+
+ while (likely(pIn < pInLimit - (STEPSIZE - 1))) {
+ size_t const diff = LZ4_read_ARCH(pMatch) ^ LZ4_read_ARCH(pIn);
+
+ if (!diff) {
+ pIn += STEPSIZE;
+ pMatch += STEPSIZE;
+ continue;
+ }
+
+ pIn += LZ4_NbCommonBytes(diff);
+
+ return (unsigned int)(pIn - pStart);
+ }
+
+#if LZ4_ARCH64
+ if ((pIn < (pInLimit - 3))
+ && (LZ4_read32(pMatch) == LZ4_read32(pIn))) {
+ pIn += 4;
+ pMatch += 4;
+ }
#endif
-#else /* 32-bit */
-#define STEPSIZE 4
+ if ((pIn < (pInLimit - 1))
+ && (LZ4_read16(pMatch) == LZ4_read16(pIn))) {
+ pIn += 2;
+ pMatch += 2;
+ }
-#define LZ4_COPYSTEP(s, d) \
- do { \
- PUT4(s, d); \
- d += 4; \
- s += 4; \
- } while (0)
+ if ((pIn < pInLimit) && (*pMatch == *pIn))
+ pIn++;
-#define LZ4_COPYPACKET(s, d) \
- do { \
- LZ4_COPYSTEP(s, d); \
- LZ4_COPYSTEP(s, d); \
- } while (0)
+ return (unsigned int)(pIn - pStart);
+}
-#define LZ4_SECURECOPY LZ4_WILDCOPY
-#define HTYPE const u8*
+typedef enum { noLimit = 0, limitedOutput = 1 } limitedOutput_directive;
+typedef enum { byPtr, byU32, byU16 } tableType_t;
-#ifdef __BIG_ENDIAN
-#define LZ4_NBCOMMONBYTES(val) (__builtin_clz(val) >> 3)
-#else
-#define LZ4_NBCOMMONBYTES(val) (__builtin_ctz(val) >> 3)
-#endif
+typedef enum { noDict = 0, withPrefix64k, usingExtDict } dict_directive;
+typedef enum { noDictIssue = 0, dictSmall } dictIssue_directive;
-#endif
+typedef enum { endOnOutputSize = 0, endOnInputSize = 1 } endCondition_directive;
+typedef enum { full = 0, partial = 1 } earlyEnd_directive;
-#define LZ4_WILDCOPY(s, d, e) \
- do { \
- LZ4_COPYPACKET(s, d); \
- } while (d < e)
-
-#define LZ4_BLINDCOPY(s, d, l) \
- do { \
- u8 *e = (d) + l; \
- LZ4_WILDCOPY(s, d, e); \
- d = e; \
- } while (0)
+#endif
diff --git a/lib/lz4/lz4hc_compress.c b/lib/lz4/lz4hc_compress.c
index f344f76b6559..e1fbf1561e55 100644
--- a/lib/lz4/lz4hc_compress.c
+++ b/lib/lz4/lz4hc_compress.c
@@ -1,19 +1,17 @@
/*
* LZ4 HC - High Compression Mode of LZ4
- * Copyright (C) 2011-2012, Yann Collet.
- * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
+ * Copyright (C) 2011-2015, Yann Collet.
*
+ * BSD 2 - Clause License (http://www.opensource.org/licenses/bsd - license.php)
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
- *
- * * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * * Redistributions in binary form must reproduce the above
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
- *
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
@@ -25,323 +23,361 @@
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- *
* You can contact the author at :
- * - LZ4 homepage : http://fastcompression.blogspot.com/p/lz4.html
- * - LZ4 source repository : http://code.google.com/p/lz4/
+ * - LZ4 homepage : http://www.lz4.org
+ * - LZ4 source repository : https://github.com/lz4/lz4
*
- * Changed for kernel use by:
- * Chanho Min <chanho.min@lge.com>
+ * Changed for kernel usage by:
+ * Sven Schmidt <4sschmid@informatik.uni-hamburg.de>
*/
-#include <linux/module.h>
-#include <linux/kernel.h>
+/*-************************************
+ * Dependencies
+ **************************************/
#include <linux/lz4.h>
-#include <asm/unaligned.h>
#include "lz4defs.h"
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/string.h> /* memset */
+
+/* *************************************
+ * Local Constants and types
+ ***************************************/
-struct lz4hc_data {
- const u8 *base;
- HTYPE hashtable[HASHTABLESIZE];
- u16 chaintable[MAXD];
- const u8 *nexttoupdate;
-} __attribute__((__packed__));
+#define OPTIMAL_ML (int)((ML_MASK - 1) + MINMATCH)
-static inline int lz4hc_init(struct lz4hc_data *hc4, const u8 *base)
+#define HASH_FUNCTION(i) (((i) * 2654435761U) \
+ >> ((MINMATCH*8) - LZ4HC_HASH_LOG))
+#define DELTANEXTU16(p) chainTable[(U16)(p)] /* faster */
+
+static U32 LZ4HC_hashPtr(const void *ptr)
+{
+ return HASH_FUNCTION(LZ4_read32(ptr));
+}
+
+/**************************************
+ * HC Compression
+ **************************************/
+static void LZ4HC_init(LZ4HC_CCtx_internal *hc4, const BYTE *start)
{
- memset((void *)hc4->hashtable, 0, sizeof(hc4->hashtable));
- memset(hc4->chaintable, 0xFF, sizeof(hc4->chaintable));
-
-#if LZ4_ARCH64
- hc4->nexttoupdate = base + 1;
-#else
- hc4->nexttoupdate = base;
-#endif
- hc4->base = base;
- return 1;
+ memset((void *)hc4->hashTable, 0, sizeof(hc4->hashTable));
+ memset(hc4->chainTable, 0xFF, sizeof(hc4->chainTable));
+ hc4->nextToUpdate = 64 * KB;
+ hc4->base = start - 64 * KB;
+ hc4->end = start;
+ hc4->dictBase = start - 64 * KB;
+ hc4->dictLimit = 64 * KB;
+ hc4->lowLimit = 64 * KB;
}
/* Update chains up to ip (excluded) */
-static inline void lz4hc_insert(struct lz4hc_data *hc4, const u8 *ip)
+static FORCE_INLINE void LZ4HC_Insert(LZ4HC_CCtx_internal *hc4,
+ const BYTE *ip)
{
- u16 *chaintable = hc4->chaintable;
- HTYPE *hashtable = hc4->hashtable;
-#if LZ4_ARCH64
+ U16 * const chainTable = hc4->chainTable;
+ U32 * const hashTable = hc4->hashTable;
const BYTE * const base = hc4->base;
-#else
- const int base = 0;
-#endif
+ U32 const target = (U32)(ip - base);
+ U32 idx = hc4->nextToUpdate;
+
+ while (idx < target) {
+ U32 const h = LZ4HC_hashPtr(base + idx);
+ size_t delta = idx - hashTable[h];
- while (hc4->nexttoupdate < ip) {
- const u8 *p = hc4->nexttoupdate;
- size_t delta = p - (hashtable[HASH_VALUE(p)] + base);
if (delta > MAX_DISTANCE)
delta = MAX_DISTANCE;
- chaintable[(size_t)(p) & MAXD_MASK] = (u16)delta;
- hashtable[HASH_VALUE(p)] = (p) - base;
- hc4->nexttoupdate++;
- }
-}
-static inline size_t lz4hc_commonlength(const u8 *p1, const u8 *p2,
- const u8 *const matchlimit)
-{
- const u8 *p1t = p1;
-
- while (p1t < matchlimit - (STEPSIZE - 1)) {
-#if LZ4_ARCH64
- u64 diff = A64(p2) ^ A64(p1t);
-#else
- u32 diff = A32(p2) ^ A32(p1t);
-#endif
- if (!diff) {
- p1t += STEPSIZE;
- p2 += STEPSIZE;
- continue;
- }
- p1t += LZ4_NBCOMMONBYTES(diff);
- return p1t - p1;
- }
-#if LZ4_ARCH64
- if ((p1t < (matchlimit-3)) && (A32(p2) == A32(p1t))) {
- p1t += 4;
- p2 += 4;
- }
-#endif
+ DELTANEXTU16(idx) = (U16)delta;
- if ((p1t < (matchlimit - 1)) && (A16(p2) == A16(p1t))) {
- p1t += 2;
- p2 += 2;
+ hashTable[h] = idx;
+ idx++;
}
- if ((p1t < matchlimit) && (*p2 == *p1t))
- p1t++;
- return p1t - p1;
+
+ hc4->nextToUpdate = target;
}
-static inline int lz4hc_insertandfindbestmatch(struct lz4hc_data *hc4,
- const u8 *ip, const u8 *const matchlimit, const u8 **matchpos)
+static FORCE_INLINE int LZ4HC_InsertAndFindBestMatch(
+ LZ4HC_CCtx_internal *hc4, /* Index table will be updated */
+ const BYTE *ip,
+ const BYTE * const iLimit,
+ const BYTE **matchpos,
+ const int maxNbAttempts)
{
- u16 *const chaintable = hc4->chaintable;
- HTYPE *const hashtable = hc4->hashtable;
- const u8 *ref;
-#if LZ4_ARCH64
+ U16 * const chainTable = hc4->chainTable;
+ U32 * const HashTable = hc4->hashTable;
const BYTE * const base = hc4->base;
-#else
- const int base = 0;
-#endif
- int nbattempts = MAX_NB_ATTEMPTS;
- size_t repl = 0, ml = 0;
- u16 delta;
+ const BYTE * const dictBase = hc4->dictBase;
+ const U32 dictLimit = hc4->dictLimit;
+ const U32 lowLimit = (hc4->lowLimit + 64 * KB > (U32)(ip - base))
+ ? hc4->lowLimit
+ : (U32)(ip - base) - (64 * KB - 1);
+ U32 matchIndex;
+ int nbAttempts = maxNbAttempts;
+ size_t ml = 0;
/* HC4 match finder */
- lz4hc_insert(hc4, ip);
- ref = hashtable[HASH_VALUE(ip)] + base;
-
- /* potential repetition */
- if (ref >= ip-4) {
- /* confirmed */
- if (A32(ref) == A32(ip)) {
- delta = (u16)(ip-ref);
- repl = ml = lz4hc_commonlength(ip + MINMATCH,
- ref + MINMATCH, matchlimit) + MINMATCH;
- *matchpos = ref;
- }
- ref -= (size_t)chaintable[(size_t)(ref) & MAXD_MASK];
- }
+ LZ4HC_Insert(hc4, ip);
+ matchIndex = HashTable[LZ4HC_hashPtr(ip)];
+
+ while ((matchIndex >= lowLimit)
+ && (nbAttempts)) {
+ nbAttempts--;
+ if (matchIndex >= dictLimit) {
+ const BYTE * const match = base + matchIndex;
+
+ if (*(match + ml) == *(ip + ml)
+ && (LZ4_read32(match) == LZ4_read32(ip))) {
+ size_t const mlt = LZ4_count(ip + MINMATCH,
+ match + MINMATCH, iLimit) + MINMATCH;
- while ((ref >= ip - MAX_DISTANCE) && nbattempts) {
- nbattempts--;
- if (*(ref + ml) == *(ip + ml)) {
- if (A32(ref) == A32(ip)) {
- size_t mlt =
- lz4hc_commonlength(ip + MINMATCH,
- ref + MINMATCH, matchlimit) + MINMATCH;
if (mlt > ml) {
ml = mlt;
- *matchpos = ref;
+ *matchpos = match;
+ }
+ }
+ } else {
+ const BYTE * const match = dictBase + matchIndex;
+
+ if (LZ4_read32(match) == LZ4_read32(ip)) {
+ size_t mlt;
+ const BYTE *vLimit = ip
+ + (dictLimit - matchIndex);
+
+ if (vLimit > iLimit)
+ vLimit = iLimit;
+ mlt = LZ4_count(ip + MINMATCH,
+ match + MINMATCH, vLimit) + MINMATCH;
+ if ((ip + mlt == vLimit)
+ && (vLimit < iLimit))
+ mlt += LZ4_count(ip + mlt,
+ base + dictLimit,
+ iLimit);
+ if (mlt > ml) {
+ /* virtual matchpos */
+ ml = mlt;
+ *matchpos = base + matchIndex;
}
}
}
- ref -= (size_t)chaintable[(size_t)(ref) & MAXD_MASK];
- }
-
- /* Complete table */
- if (repl) {
- const BYTE *ptr = ip;
- const BYTE *end;
- end = ip + repl - (MINMATCH-1);
- /* Pre-Load */
- while (ptr < end - delta) {
- chaintable[(size_t)(ptr) & MAXD_MASK] = delta;
- ptr++;
- }
- do {
- chaintable[(size_t)(ptr) & MAXD_MASK] = delta;
- /* Head of chain */
- hashtable[HASH_VALUE(ptr)] = (ptr) - base;
- ptr++;
- } while (ptr < end);
- hc4->nexttoupdate = end;
+ matchIndex -= DELTANEXTU16(matchIndex);
}
return (int)ml;
}
-static inline int lz4hc_insertandgetwidermatch(struct lz4hc_data *hc4,
- const u8 *ip, const u8 *startlimit, const u8 *matchlimit, int longest,
- const u8 **matchpos, const u8 **startpos)
+static FORCE_INLINE int LZ4HC_InsertAndGetWiderMatch(
+ LZ4HC_CCtx_internal *hc4,
+ const BYTE * const ip,
+ const BYTE * const iLowLimit,
+ const BYTE * const iHighLimit,
+ int longest,
+ const BYTE **matchpos,
+ const BYTE **startpos,
+ const int maxNbAttempts)
{
- u16 *const chaintable = hc4->chaintable;
- HTYPE *const hashtable = hc4->hashtable;
-#if LZ4_ARCH64
+ U16 * const chainTable = hc4->chainTable;
+ U32 * const HashTable = hc4->hashTable;
const BYTE * const base = hc4->base;
-#else
- const int base = 0;
-#endif
- const u8 *ref;
- int nbattempts = MAX_NB_ATTEMPTS;
- int delta = (int)(ip - startlimit);
+ const U32 dictLimit = hc4->dictLimit;
+ const BYTE * const lowPrefixPtr = base + dictLimit;
+ const U32 lowLimit = (hc4->lowLimit + 64 * KB > (U32)(ip - base))
+ ? hc4->lowLimit
+ : (U32)(ip - base) - (64 * KB - 1);
+ const BYTE * const dictBase = hc4->dictBase;
+ U32 matchIndex;
+ int nbAttempts = maxNbAttempts;
+ int delta = (int)(ip - iLowLimit);
/* First Match */
- lz4hc_insert(hc4, ip);
- ref = hashtable[HASH_VALUE(ip)] + base;
-
- while ((ref >= ip - MAX_DISTANCE) && (ref >= hc4->base)
- && (nbattempts)) {
- nbattempts--;
- if (*(startlimit + longest) == *(ref - delta + longest)) {
- if (A32(ref) == A32(ip)) {
- const u8 *reft = ref + MINMATCH;
- const u8 *ipt = ip + MINMATCH;
- const u8 *startt = ip;
-
- while (ipt < matchlimit-(STEPSIZE - 1)) {
- #if LZ4_ARCH64
- u64 diff = A64(reft) ^ A64(ipt);
- #else
- u32 diff = A32(reft) ^ A32(ipt);
- #endif
-
- if (!diff) {
- ipt += STEPSIZE;
- reft += STEPSIZE;
- continue;
+ LZ4HC_Insert(hc4, ip);
+ matchIndex = HashTable[LZ4HC_hashPtr(ip)];
+
+ while ((matchIndex >= lowLimit)
+ && (nbAttempts)) {
+ nbAttempts--;
+ if (matchIndex >= dictLimit) {
+ const BYTE *matchPtr = base + matchIndex;
+
+ if (*(iLowLimit + longest)
+ == *(matchPtr - delta + longest)) {
+ if (LZ4_read32(matchPtr) == LZ4_read32(ip)) {
+ int mlt = MINMATCH + LZ4_count(
+ ip + MINMATCH,
+ matchPtr + MINMATCH,
+ iHighLimit);
+ int back = 0;
+
+ while ((ip + back > iLowLimit)
+ && (matchPtr + back > lowPrefixPtr)
+ && (ip[back - 1] == matchPtr[back - 1]))
+ back--;
+
+ mlt -= back;
+
+ if (mlt > longest) {
+ longest = (int)mlt;
+ *matchpos = matchPtr + back;
+ *startpos = ip + back;
}
- ipt += LZ4_NBCOMMONBYTES(diff);
- goto _endcount;
- }
- #if LZ4_ARCH64
- if ((ipt < (matchlimit - 3))
- && (A32(reft) == A32(ipt))) {
- ipt += 4;
- reft += 4;
}
- ipt += 2;
- #endif
- if ((ipt < (matchlimit - 1))
- && (A16(reft) == A16(ipt))) {
- reft += 2;
- }
- if ((ipt < matchlimit) && (*reft == *ipt))
- ipt++;
-_endcount:
- reft = ref;
-
- while ((startt > startlimit)
- && (reft > hc4->base)
- && (startt[-1] == reft[-1])) {
- startt--;
- reft--;
- }
-
- if ((ipt - startt) > longest) {
- longest = (int)(ipt - startt);
- *matchpos = reft;
- *startpos = startt;
+ }
+ } else {
+ const BYTE * const matchPtr = dictBase + matchIndex;
+
+ if (LZ4_read32(matchPtr) == LZ4_read32(ip)) {
+ size_t mlt;
+ int back = 0;
+ const BYTE *vLimit = ip + (dictLimit - matchIndex);
+
+ if (vLimit > iHighLimit)
+ vLimit = iHighLimit;
+
+ mlt = LZ4_count(ip + MINMATCH,
+ matchPtr + MINMATCH, vLimit) + MINMATCH;
+
+ if ((ip + mlt == vLimit) && (vLimit < iHighLimit))
+ mlt += LZ4_count(ip + mlt, base + dictLimit,
+ iHighLimit);
+ while ((ip + back > iLowLimit)
+ && (matchIndex + back > lowLimit)
+ && (ip[back - 1] == matchPtr[back - 1]))
+ back--;
+
+ mlt -= back;
+
+ if ((int)mlt > longest) {
+ longest = (int)mlt;
+ *matchpos = base + matchIndex + back;
+ *startpos = ip + back;
}
}
}
- ref -= (size_t)chaintable[(size_t)(ref) & MAXD_MASK];
+
+ matchIndex -= DELTANEXTU16(matchIndex);
}
+
return longest;
}
-static inline int lz4_encodesequence(const u8 **ip, u8 **op, const u8 **anchor,
- int ml, const u8 *ref)
+static FORCE_INLINE int LZ4HC_encodeSequence(
+ const BYTE **ip,
+ BYTE **op,
+ const BYTE **anchor,
+ int matchLength,
+ const BYTE * const match,
+ limitedOutput_directive limitedOutputBuffer,
+ BYTE *oend)
{
- int length, len;
- u8 *token;
+ int length;
+ BYTE *token;
/* Encode Literal length */
length = (int)(*ip - *anchor);
token = (*op)++;
+
+ if ((limitedOutputBuffer)
+ && ((*op + (length>>8)
+ + length + (2 + 1 + LASTLITERALS)) > oend)) {
+ /* Check output limit */
+ return 1;
+ }
if (length >= (int)RUN_MASK) {
- *token = (RUN_MASK << ML_BITS);
+ int len;
+
+ *token = (RUN_MASK<<ML_BITS);
len = length - RUN_MASK;
for (; len > 254 ; len -= 255)
*(*op)++ = 255;
- *(*op)++ = (u8)len;
+ *(*op)++ = (BYTE)len;
} else
- *token = (length << ML_BITS);
+ *token = (BYTE)(length<<ML_BITS);
/* Copy Literals */
- LZ4_BLINDCOPY(*anchor, *op, length);
+ LZ4_wildCopy(*op, *anchor, (*op) + length);
+ *op += length;
/* Encode Offset */
- LZ4_WRITE_LITTLEENDIAN_16(*op, (u16)(*ip - ref));
+ LZ4_writeLE16(*op, (U16)(*ip - match));
+ *op += 2;
/* Encode MatchLength */
- len = (int)(ml - MINMATCH);
- if (len >= (int)ML_MASK) {
+ length = (int)(matchLength - MINMATCH);
+
+ if ((limitedOutputBuffer)
+ && (*op + (length>>8)
+ + (1 + LASTLITERALS) > oend)) {
+ /* Check output limit */
+ return 1;
+ }
+
+ if (length >= (int)ML_MASK) {
*token += ML_MASK;
- len -= ML_MASK;
- for (; len > 509 ; len -= 510) {
+ length -= ML_MASK;
+
+ for (; length > 509 ; length -= 510) {
*(*op)++ = 255;
*(*op)++ = 255;
}
- if (len > 254) {
- len -= 255;
+
+ if (length > 254) {
+ length -= 255;
*(*op)++ = 255;
}
- *(*op)++ = (u8)len;
+
+ *(*op)++ = (BYTE)length;
} else
- *token += len;
+ *token += (BYTE)(length);
/* Prepare next loop */
- *ip += ml;
+ *ip += matchLength;
*anchor = *ip;
return 0;
}
-static int lz4_compresshcctx(struct lz4hc_data *ctx,
- const char *source,
- char *dest,
- int isize)
+static int LZ4HC_compress_generic(
+ LZ4HC_CCtx_internal *const ctx,
+ const char * const source,
+ char * const dest,
+ int const inputSize,
+ int const maxOutputSize,
+ int compressionLevel,
+ limitedOutput_directive limit
+ )
{
- const u8 *ip = (const u8 *)source;
- const u8 *anchor = ip;
- const u8 *const iend = ip + isize;
- const u8 *const mflimit = iend - MFLIMIT;
- const u8 *const matchlimit = (iend - LASTLITERALS);
+ const BYTE *ip = (const BYTE *) source;
+ const BYTE *anchor = ip;
+ const BYTE * const iend = ip + inputSize;
+ const BYTE * const mflimit = iend - MFLIMIT;
+ const BYTE * const matchlimit = (iend - LASTLITERALS);
- u8 *op = (u8 *)dest;
+ BYTE *op = (BYTE *) dest;
+ BYTE * const oend = op + maxOutputSize;
+ unsigned int maxNbAttempts;
int ml, ml2, ml3, ml0;
- const u8 *ref = NULL;
- const u8 *start2 = NULL;
- const u8 *ref2 = NULL;
- const u8 *start3 = NULL;
- const u8 *ref3 = NULL;
- const u8 *start0;
- const u8 *ref0;
- int lastrun;
+ const BYTE *ref = NULL;
+ const BYTE *start2 = NULL;
+ const BYTE *ref2 = NULL;
+ const BYTE *start3 = NULL;
+ const BYTE *ref3 = NULL;
+ const BYTE *start0;
+ const BYTE *ref0;
+
+ /* init */
+ if (compressionLevel > LZ4HC_MAX_CLEVEL)
+ compressionLevel = LZ4HC_MAX_CLEVEL;
+ if (compressionLevel < 1)
+ compressionLevel = LZ4HC_DEFAULT_CLEVEL;
+ maxNbAttempts = 1 << (compressionLevel - 1);
+ ctx->end += inputSize;
ip++;
/* Main Loop */
while (ip < mflimit) {
- ml = lz4hc_insertandfindbestmatch(ctx, ip, matchlimit, (&ref));
+ ml = LZ4HC_InsertAndFindBestMatch(ctx, ip,
+ matchlimit, (&ref), maxNbAttempts);
if (!ml) {
ip++;
continue;
@@ -351,51 +387,59 @@ static int lz4_compresshcctx(struct lz4hc_data *ctx,
start0 = ip;
ref0 = ref;
ml0 = ml;
-_search2:
- if (ip+ml < mflimit)
- ml2 = lz4hc_insertandgetwidermatch(ctx, ip + ml - 2,
- ip + 1, matchlimit, ml, &ref2, &start2);
+
+_Search2:
+ if (ip + ml < mflimit)
+ ml2 = LZ4HC_InsertAndGetWiderMatch(ctx,
+ ip + ml - 2, ip + 0,
+ matchlimit, ml, &ref2,
+ &start2, maxNbAttempts);
else
ml2 = ml;
- /* No better match */
+
if (ml2 == ml) {
- lz4_encodesequence(&ip, &op, &anchor, ml, ref);
+ /* No better match */
+ if (LZ4HC_encodeSequence(&ip, &op,
+ &anchor, ml, ref, limit, oend))
+ return 0;
continue;
}
if (start0 < ip) {
- /* empirical */
if (start2 < ip + ml0) {
+ /* empirical */
ip = start0;
ref = ref0;
ml = ml0;
}
}
- /*
- * Here, start0==ip
- * First Match too small : removed
- */
+
+ /* Here, start0 == ip */
if ((start2 - ip) < 3) {
+ /* First Match too small : removed */
ml = ml2;
ip = start2;
ref = ref2;
- goto _search2;
+ goto _Search2;
}
-_search3:
+_Search3:
/*
- * Currently we have :
- * ml2 > ml1, and
- * ip1+3 <= ip2 (usually < ip1+ml1)
- */
+ * Currently we have :
+ * ml2 > ml1, and
+ * ip1 + 3 <= ip2 (usually < ip1 + ml1)
+ */
if ((start2 - ip) < OPTIMAL_ML) {
int correction;
int new_ml = ml;
+
if (new_ml > OPTIMAL_ML)
new_ml = OPTIMAL_ML;
if (ip + new_ml > start2 + ml2 - MINMATCH)
new_ml = (int)(start2 - ip) + ml2 - MINMATCH;
+
correction = new_ml - (int)(start2 - ip);
+
if (correction > 0) {
start2 += correction;
ref2 += correction;
@@ -403,39 +447,44 @@ _search3:
}
}
/*
- * Now, we have start2 = ip+new_ml,
- * with new_ml=min(ml, OPTIMAL_ML=18)
+ * Now, we have start2 = ip + new_ml,
+ * with new_ml = min(ml, OPTIMAL_ML = 18)
*/
+
if (start2 + ml2 < mflimit)
- ml3 = lz4hc_insertandgetwidermatch(ctx,
- start2 + ml2 - 3, start2, matchlimit,
- ml2, &ref3, &start3);
+ ml3 = LZ4HC_InsertAndGetWiderMatch(ctx,
+ start2 + ml2 - 3, start2,
+ matchlimit, ml2, &ref3, &start3,
+ maxNbAttempts);
else
ml3 = ml2;
- /* No better match : 2 sequences to encode */
if (ml3 == ml2) {
+ /* No better match : 2 sequences to encode */
/* ip & ref are known; Now for ml */
- if (start2 < ip+ml)
+ if (start2 < ip + ml)
ml = (int)(start2 - ip);
-
/* Now, encode 2 sequences */
- lz4_encodesequence(&ip, &op, &anchor, ml, ref);
+ if (LZ4HC_encodeSequence(&ip, &op, &anchor,
+ ml, ref, limit, oend))
+ return 0;
ip = start2;
- lz4_encodesequence(&ip, &op, &anchor, ml2, ref2);
+ if (LZ4HC_encodeSequence(&ip, &op, &anchor,
+ ml2, ref2, limit, oend))
+ return 0;
continue;
}
- /* Not enough space for match 2 : remove it */
if (start3 < ip + ml + 3) {
- /*
- * can write Seq1 immediately ==> Seq2 is removed,
- * so Seq3 becomes Seq1
- */
+ /* Not enough space for match 2 : remove it */
if (start3 >= (ip + ml)) {
+ /* can write Seq1 immediately
+ * ==> Seq2 is removed,
+ * so Seq3 becomes Seq1
+ */
if (start2 < ip + ml) {
- int correction =
- (int)(ip + ml - start2);
+ int correction = (int)(ip + ml - start2);
+
start2 += correction;
ref2 += correction;
ml2 -= correction;
@@ -446,35 +495,38 @@ _search3:
}
}
- lz4_encodesequence(&ip, &op, &anchor, ml, ref);
- ip = start3;
+ if (LZ4HC_encodeSequence(&ip, &op, &anchor,
+ ml, ref, limit, oend))
+ return 0;
+ ip = start3;
ref = ref3;
- ml = ml3;
+ ml = ml3;
start0 = start2;
ref0 = ref2;
ml0 = ml2;
- goto _search2;
+ goto _Search2;
}
start2 = start3;
ref2 = ref3;
ml2 = ml3;
- goto _search3;
+ goto _Search3;
}
/*
- * OK, now we have 3 ascending matches; let's write at least
- * the first one ip & ref are known; Now for ml
- */
+ * OK, now we have 3 ascending matches;
+ * let's write at least the first one
+ * ip & ref are known; Now for ml
+ */
if (start2 < ip + ml) {
if ((start2 - ip) < (int)ML_MASK) {
int correction;
+
if (ml > OPTIMAL_ML)
ml = OPTIMAL_ML;
if (ip + ml > start2 + ml2 - MINMATCH)
- ml = (int)(start2 - ip) + ml2
- - MINMATCH;
+ ml = (int)(start2 - ip) + ml2 - MINMATCH;
correction = ml - (int)(start2 - ip);
if (correction > 0) {
start2 += correction;
@@ -484,7 +536,9 @@ _search3:
} else
ml = (int)(start2 - ip);
}
- lz4_encodesequence(&ip, &op, &anchor, ml, ref);
+ if (LZ4HC_encodeSequence(&ip, &op, &anchor, ml,
+ ref, limit, oend))
+ return 0;
ip = start2;
ref = ref2;
@@ -494,46 +548,245 @@ _search3:
ref2 = ref3;
ml2 = ml3;
- goto _search3;
+ goto _Search3;
}
/* Encode Last Literals */
- lastrun = (int)(iend - anchor);
- if (lastrun >= (int)RUN_MASK) {
- *op++ = (RUN_MASK << ML_BITS);
- lastrun -= RUN_MASK;
- for (; lastrun > 254 ; lastrun -= 255)
- *op++ = 255;
- *op++ = (u8) lastrun;
- } else
- *op++ = (lastrun << ML_BITS);
- memcpy(op, anchor, iend - anchor);
- op += iend - anchor;
+ {
+ int lastRun = (int)(iend - anchor);
+
+ if ((limit)
+ && (((char *)op - dest) + lastRun + 1
+ + ((lastRun + 255 - RUN_MASK)/255)
+ > (U32)maxOutputSize)) {
+ /* Check output limit */
+ return 0;
+ }
+ if (lastRun >= (int)RUN_MASK) {
+ *op++ = (RUN_MASK<<ML_BITS);
+ lastRun -= RUN_MASK;
+ for (; lastRun > 254 ; lastRun -= 255)
+ *op++ = 255;
+ *op++ = (BYTE) lastRun;
+ } else
+ *op++ = (BYTE)(lastRun<<ML_BITS);
+ memcpy(op, anchor, iend - anchor);
+ op += iend - anchor;
+ }
+
/* End */
return (int) (((char *)op) - dest);
}
-int lz4hc_compress(const unsigned char *src, size_t src_len,
- unsigned char *dst, size_t *dst_len, void *wrkmem)
+static int LZ4_compress_HC_extStateHC(
+ void *state,
+ const char *src,
+ char *dst,
+ int srcSize,
+ int maxDstSize,
+ int compressionLevel)
{
- int ret = -1;
- int out_len = 0;
+ LZ4HC_CCtx_internal *ctx = &((LZ4_streamHC_t *)state)->internal_donotuse;
- struct lz4hc_data *hc4 = (struct lz4hc_data *)wrkmem;
- lz4hc_init(hc4, (const u8 *)src);
- out_len = lz4_compresshcctx((struct lz4hc_data *)hc4, (const u8 *)src,
- (char *)dst, (int)src_len);
+ if (((size_t)(state)&(sizeof(void *) - 1)) != 0) {
+ /* Error : state is not aligned
+ * for pointers (32 or 64 bits)
+ */
+ return 0;
+ }
- if (out_len < 0)
- goto exit;
+ LZ4HC_init(ctx, (const BYTE *)src);
- *dst_len = out_len;
- return 0;
+ if (maxDstSize < LZ4_compressBound(srcSize))
+ return LZ4HC_compress_generic(ctx, src, dst,
+ srcSize, maxDstSize, compressionLevel, limitedOutput);
+ else
+ return LZ4HC_compress_generic(ctx, src, dst,
+ srcSize, maxDstSize, compressionLevel, noLimit);
+}
+
+int LZ4_compress_HC(const char *src, char *dst, int srcSize,
+ int maxDstSize, int compressionLevel, void *wrkmem)
+{
+ return LZ4_compress_HC_extStateHC(wrkmem, src, dst,
+ srcSize, maxDstSize, compressionLevel);
+}
+EXPORT_SYMBOL(LZ4_compress_HC);
+
+/**************************************
+ * Streaming Functions
+ **************************************/
+void LZ4_resetStreamHC(LZ4_streamHC_t *LZ4_streamHCPtr, int compressionLevel)
+{
+ LZ4_streamHCPtr->internal_donotuse.base = NULL;
+ LZ4_streamHCPtr->internal_donotuse.compressionLevel = (unsigned int)compressionLevel;
+}
+
+int LZ4_loadDictHC(LZ4_streamHC_t *LZ4_streamHCPtr,
+ const char *dictionary,
+ int dictSize)
+{
+ LZ4HC_CCtx_internal *ctxPtr = &LZ4_streamHCPtr->internal_donotuse;
+
+ if (dictSize > 64 * KB) {
+ dictionary += dictSize - 64 * KB;
+ dictSize = 64 * KB;
+ }
+ LZ4HC_init(ctxPtr, (const BYTE *)dictionary);
+ if (dictSize >= 4)
+ LZ4HC_Insert(ctxPtr, (const BYTE *)dictionary + (dictSize - 3));
+ ctxPtr->end = (const BYTE *)dictionary + dictSize;
+ return dictSize;
+}
+EXPORT_SYMBOL(LZ4_loadDictHC);
+
+/* compression */
+
+static void LZ4HC_setExternalDict(
+ LZ4HC_CCtx_internal *ctxPtr,
+ const BYTE *newBlock)
+{
+ if (ctxPtr->end >= ctxPtr->base + 4) {
+ /* Referencing remaining dictionary content */
+ LZ4HC_Insert(ctxPtr, ctxPtr->end - 3);
+ }
+
+ /*
+ * Only one memory segment for extDict,
+ * so any previous extDict is lost at this stage
+ */
+ ctxPtr->lowLimit = ctxPtr->dictLimit;
+ ctxPtr->dictLimit = (U32)(ctxPtr->end - ctxPtr->base);
+ ctxPtr->dictBase = ctxPtr->base;
+ ctxPtr->base = newBlock - ctxPtr->dictLimit;
+ ctxPtr->end = newBlock;
+ /* match referencing will resume from there */
+ ctxPtr->nextToUpdate = ctxPtr->dictLimit;
+}
+EXPORT_SYMBOL(LZ4HC_setExternalDict);
+
+static int LZ4_compressHC_continue_generic(
+ LZ4_streamHC_t *LZ4_streamHCPtr,
+ const char *source,
+ char *dest,
+ int inputSize,
+ int maxOutputSize,
+ limitedOutput_directive limit)
+{
+ LZ4HC_CCtx_internal *ctxPtr = &LZ4_streamHCPtr->internal_donotuse;
+
+ /* auto - init if forgotten */
+ if (ctxPtr->base == NULL)
+ LZ4HC_init(ctxPtr, (const BYTE *) source);
+
+ /* Check overflow */
+ if ((size_t)(ctxPtr->end - ctxPtr->base) > 2 * GB) {
+ size_t dictSize = (size_t)(ctxPtr->end - ctxPtr->base)
+ - ctxPtr->dictLimit;
+ if (dictSize > 64 * KB)
+ dictSize = 64 * KB;
+ LZ4_loadDictHC(LZ4_streamHCPtr,
+ (const char *)(ctxPtr->end) - dictSize, (int)dictSize);
+ }
+
+ /* Check if blocks follow each other */
+ if ((const BYTE *)source != ctxPtr->end)
+ LZ4HC_setExternalDict(ctxPtr, (const BYTE *)source);
+
+ /* Check overlapping input/dictionary space */
+ {
+ const BYTE *sourceEnd = (const BYTE *) source + inputSize;
+ const BYTE * const dictBegin = ctxPtr->dictBase + ctxPtr->lowLimit;
+ const BYTE * const dictEnd = ctxPtr->dictBase + ctxPtr->dictLimit;
+
+ if ((sourceEnd > dictBegin)
+ && ((const BYTE *)source < dictEnd)) {
+ if (sourceEnd > dictEnd)
+ sourceEnd = dictEnd;
+ ctxPtr->lowLimit = (U32)(sourceEnd - ctxPtr->dictBase);
+
+ if (ctxPtr->dictLimit - ctxPtr->lowLimit < 4)
+ ctxPtr->lowLimit = ctxPtr->dictLimit;
+ }
+ }
+
+ return LZ4HC_compress_generic(ctxPtr, source, dest,
+ inputSize, maxOutputSize, ctxPtr->compressionLevel, limit);
+}
+
+int LZ4_compress_HC_continue(
+ LZ4_streamHC_t *LZ4_streamHCPtr,
+ const char *source,
+ char *dest,
+ int inputSize,
+ int maxOutputSize)
+{
+ if (maxOutputSize < LZ4_compressBound(inputSize))
+ return LZ4_compressHC_continue_generic(LZ4_streamHCPtr,
+ source, dest, inputSize, maxOutputSize, limitedOutput);
+ else
+ return LZ4_compressHC_continue_generic(LZ4_streamHCPtr,
+ source, dest, inputSize, maxOutputSize, noLimit);
+}
+EXPORT_SYMBOL(LZ4_compress_HC_continue);
+
+/* dictionary saving */
+
+int LZ4_saveDictHC(
+ LZ4_streamHC_t *LZ4_streamHCPtr,
+ char *safeBuffer,
+ int dictSize)
+{
+ LZ4HC_CCtx_internal *const streamPtr = &LZ4_streamHCPtr->internal_donotuse;
+ int const prefixSize = (int)(streamPtr->end
+ - (streamPtr->base + streamPtr->dictLimit));
+
+ if (dictSize > 64 * KB)
+ dictSize = 64 * KB;
+ if (dictSize < 4)
+ dictSize = 0;
+ if (dictSize > prefixSize)
+ dictSize = prefixSize;
+
+ memmove(safeBuffer, streamPtr->end - dictSize, dictSize);
-exit:
- return ret;
+ {
+ U32 const endIndex = (U32)(streamPtr->end - streamPtr->base);
+
+ streamPtr->end = (const BYTE *)safeBuffer + dictSize;
+ streamPtr->base = streamPtr->end - endIndex;
+ streamPtr->dictLimit = endIndex - dictSize;
+ streamPtr->lowLimit = endIndex - dictSize;
+
+ if (streamPtr->nextToUpdate < streamPtr->dictLimit)
+ streamPtr->nextToUpdate = streamPtr->dictLimit;
+ }
+ return dictSize;
+}
+EXPORT_SYMBOL(LZ4_saveDictHC);
+
+/*-******************************
+ * For backwards compatibility
+ ********************************/
+int lz4hc_compress(const unsigned char *src, size_t src_len,
+ unsigned char *dst, size_t *dst_len, void *wrkmem)
+{
+ *dst_len = LZ4_compress_HC(src, dst, src_len,
+ *dst_len, LZ4HC_DEFAULT_CLEVEL, wrkmem);
+
+ /*
+ * Prior lz4hc_compress will return -1 in case of error
+ * and 0 on success
+ * while new LZ4_compress_HC
+ * returns 0 in case of error
+ * and the output length on success
+ */
+ if (!*dst_len)
+ return -1;
+ else
+ return 0;
}
EXPORT_SYMBOL(lz4hc_compress);
MODULE_LICENSE("Dual BSD/GPL");
-MODULE_DESCRIPTION("LZ4HC compressor");
+MODULE_DESCRIPTION("LZ4 HC compressor");